U.S. patent number 10,571,963 [Application Number 15/760,333] was granted by the patent office on 2020-02-25 for housing.
This patent grant is currently assigned to TORAY INDUSTRIES, INC.. The grantee listed for this patent is TORAY INDUSTRIES, INC.. Invention is credited to Takashi Fujioka, Masato Honma.
United States Patent |
10,571,963 |
Honma , et al. |
February 25, 2020 |
Housing
Abstract
A housing includes: a top cover; a bottom cover having a rising
wall member erected toward the top cover and joined to the top
cover at a rim; and a reinforcing structure which is disposed in a
space divided by the top cover and the bottom cover, and has an
opening, the reinforcing structure being joined to the bottom
cover. The bottom cover is formed of a material having a thickness
of 0.1 mm or more and 0.8 mm or less and an elastic modulus of 20
GPa or more and 120 GPa or less.
Inventors: |
Honma; Masato (Ehime,
JP), Fujioka; Takashi (Ehime, JP) |
Applicant: |
Name |
City |
State |
Country |
Type |
TORAY INDUSTRIES, INC. |
Tokyo |
N/A |
JP |
|
|
Assignee: |
TORAY INDUSTRIES, INC. (Tokyo,
JP)
|
Family
ID: |
58289244 |
Appl.
No.: |
15/760,333 |
Filed: |
September 6, 2016 |
PCT
Filed: |
September 06, 2016 |
PCT No.: |
PCT/JP2016/076116 |
371(c)(1),(2),(4) Date: |
March 15, 2018 |
PCT
Pub. No.: |
WO2017/047439 |
PCT
Pub. Date: |
March 23, 2017 |
Prior Publication Data
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|
|
|
Document
Identifier |
Publication Date |
|
US 20180299925 A1 |
Oct 18, 2018 |
|
Foreign Application Priority Data
|
|
|
|
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Sep 18, 2015 [JP] |
|
|
2015-185985 |
Sep 18, 2015 [JP] |
|
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2015-185987 |
Sep 18, 2015 [JP] |
|
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2015-185992 |
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04M
1/185 (20130101); G06F 1/1628 (20130101); G06F
1/1637 (20130101); G06F 1/1626 (20130101); H04M
1/0249 (20130101); H04M 1/026 (20130101); H04B
1/3888 (20130101); G06F 1/1603 (20130101); G06F
1/1656 (20130101); H04M 1/0202 (20130101) |
Current International
Class: |
G06F
1/16 (20060101); H04B 1/3888 (20150101); H04M
1/02 (20060101) |
Field of
Search: |
;455/575.8 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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|
|
|
|
|
|
102341429 |
|
Feb 2012 |
|
CN |
|
104470715 |
|
Mar 2015 |
|
CN |
|
104781065 |
|
Jul 2015 |
|
CN |
|
8-288681 |
|
Nov 1996 |
|
JP |
|
10-150280 |
|
Jun 1998 |
|
JP |
|
2003-101250 |
|
Apr 2003 |
|
JP |
|
2007-305041 |
|
Nov 2007 |
|
JP |
|
2009-218444 |
|
Sep 2009 |
|
JP |
|
2011-22848 |
|
Feb 2011 |
|
JP |
|
2013-74043 |
|
Apr 2013 |
|
JP |
|
2017-59791 |
|
Mar 2017 |
|
JP |
|
2017-59793 |
|
Mar 2017 |
|
JP |
|
WO 2010/109957 |
|
Sep 2010 |
|
WO |
|
WO 2015/119064 |
|
Aug 2015 |
|
WO |
|
Other References
International Search Report, issued in PCT/JP2016/076116,
PCT/ISA/210, dated Oct. 18, 2016. cited by applicant .
Written Opinion of the International Searching Authority, issued in
PCT/JP2016/076116, PCT/ISA/237, dated Oct. 18, 2016. cited by
applicant .
Extended European Search Report dated Mar. 27, 2019, in European
Patent Application No. 16846310.7. cited by applicant .
Chinese Office Action and Search Report for Chinese Application No.
201680053896.7, dated Aug. 20, 2019, with English translation of
the Office Action Action. cited by applicant .
Japanese Office Action for Japanese Application No. 2015-185985,
dated Oct. 1, 2019, with English translation. cited by applicant
.
Japanese Office Action for Japanese Application No. 2015-185987,
dated Oct. 1, 2019, with English translation. cited by applicant
.
Japanese Office Action for Japanese Application No. 2015-185992,
dated Oct. 1, 2019, with English translation. cited by
applicant.
|
Primary Examiner: Yun; Eugene
Attorney, Agent or Firm: Birch, Stewart, Kolasch &
Birch, LLP
Claims
The invention claimed is:
1. A housing comprising: a top cover; a bottom cover having a flat
portion and a rising wall member erected from a rim of the flat
portion toward the top cover and joined to the top cover; and a
reinforcing structure which is disposed in a space divided by the
top cover and the bottom cover, wherein the bottom cover is formed
of a material having a thickness of 0.1 mm or more and 0.8 mm or
less and an elastic modulus of 20 GPa or more and 120 GPa or less,
wherein the reinforcing structure includes: a flat portion or a
curved portion; and a rising wall member erected on a rim of the
flat portion or on a rim of the curved portion, and wherein the
reinforcing structure is joined to the bottom cover with a hollow
structure formed between the flat portion or the curved portion of
the reinforcing structure and the flat portion of the bottom
cover.
2. The housing according to claim 1, wherein the reinforcing
structure is formed of a material having a thickness of 0.3 mm or
more and 0.8 mm or less, and an elastic modulus of 20 GPa or more
and 120 GPa or less.
3. The housing according to claim 1, wherein the reinforcing
structure, and the top cover or the bottom cover to which the
reinforcing structure is joined are formed of a fiber-reinforced
composite material that is a cured product of a laminate of
prepregs including a reinforcing fiber and a matrix resin.
4. The housing according to claim 1, wherein the reinforcing
structure is joined to the bottom cover by thermal welding.
5. The housing according to claim 1, wherein the reinforcing
structure is joined to the bottom cover in such a manner that the
peeling load at 23.degree. C. is within a range of 60 N/cm.sup.2 or
more and 5000 N/cm.sup.2 or less, and the peeling load at
200.degree. C. is within a range of less than 60 N/cm.sup.2.
6. The housing according to claim 1, wherein the reinforcing
structure is joined directly to the bottom cover.
7. The housing according to claim 1, wherein the projected area of
the reinforcing structure in a direction of the bottom cover which
is joined to the reinforcing structure is within a range of 60% or
more and 95% or less of the area of the bottom cover to which the
reinforcing structure is joined.
8. The housing according to claim 1, wherein the volume of a hollow
structure formed by joining the reinforcing structure to the bottom
cover is within a range of 55% or more and 95% or less of the
volume of the space.
9. The housing according to claim 1, wherein a heat generation
member is disposed on a surface of the reinforcing structure on the
hollow structure side.
10. The housing according to claim 1, wherein another reinforcing
structure connecting the inner surface of the reinforcing structure
and the bottom cover to which the reinforcing structure is joined
is provided in a hollow structure formed between the reinforcing
structure and the bottom cover to which the reinforcing structure
is joined.
11. A housing comprising: a top cover; a bottom cover having a flat
portion and a rising wall member erected from a rim of the flat
portion toward the top cover and joined to the top cover at a rim;
and a reinforcing structure which is disposed in a space divided by
the top cover and the bottom cover, wherein the bottom cover is
formed of a fiber-reinforced composite material that is a cured
product of a laminate of prepregs including a reinforcing fiber and
a matrix resin, wherein the reinforcing structure includes: a flat
portion or a curved portion; and a rising wall member erected on a
rim of the flat portion or on a rim of the curved portion, and
wherein the reinforcing structure is joined to the bottom cover
with a hollow structure formed between the flat portion or the
curved portion of the reinforcing structure and the flat portion of
the bottom cover.
12. A housing comprising: a top cover; a bottom cover having a flat
portion and a rising wall member erected from a rim of the flat
portion toward the top cover and joined to the top cover at a rim;
and a reinforcing structure which is disposed in a space divided by
the top cover and the bottom cover, wherein the reinforcing
structure is formed of a material having a thickness of 0.3 mm or
more and 0.8 mm or less and an elastic modulus of 20 GPa or more
and 120 GPa or less, wherein the reinforcing structure includes: a
flat portion or a curved portion; and a rising wall member erected
on a rim of the flat portion or on a rim of the curved portion, and
wherein the reinforcing structure is joined to the bottom cover
with a hollow structure formed between the flat portion or the
curved portion of the reinforcing structure and the flat portion of
the bottom cover.
13. The housing according to claim 12, wherein the bottom cover is
formed of a material having a thickness of 0.1 mm or more and 0.8
mm or less, and an elastic modulus of 20 GPa or more and 120 GPa or
less.
14. A housing comprising: a top cover; a bottom cover having a flat
portion and a rising wall member erected from a rim of the flat
portion toward the top cover and joined to the top cover at a rim;
and a reinforcing structure which is disposed in a space divided by
the top cover and the bottom cover, wherein the reinforcing
structure is formed of a fiber-reinforced composite material that
is a cured product of a laminate of prepregs including a
reinforcing fiber and a matrix resin, wherein the reinforcing
structure includes: a flat portion or a curved portion; and a
rising wall member erected on a rim of the flat portion or on a rim
of the curved portion, and wherein the reinforcing structure is
joined to the bottom cover with a hollow structure formed between
the flat portion or the curved portion of the reinforcing structure
and the flat portion of the bottom cover.
15. A housing comprising: a top cover; a bottom cover having a flat
portion and a rising wall member erected from a rim of the flat
portion toward the top cover and joined to the top cover at a rim;
and a reinforcing structure which is disposed in a space divided by
the top cover and the bottom cover, wherein the reinforcing
structure includes: a flat portion or a curved portion; and a
rising wall member erected on a rim of the flat portion or on a rim
of the curved portion, wherein the reinforcing structure is joined
to the bottom cover or the top cover with a hollow structure formed
between the reinforcing structure and the bottom cover or the top
cover, and wherein a ratio of the linear expansion coefficient of
the reinforcing structure to the linear expansion coefficient of
the bottom cover or the top cover which is joined to the
reinforcing structure is within a range of 0.1 or more and 10 or
less.
16. A housing comprising: a top cover; a bottom cover having a flat
portion and a rising wall member erected from a rim of the flat
portion toward the top cover and joined to the top cover at a rim;
and a reinforcing structure which is disposed in a space divided by
the top cover and the bottom cover, wherein the reinforcing
structure includes: a flat portion or a curved portion; and a
rising wall member erected on a rim of the flat portion or on a rim
of the curved portion, wherein the reinforcing structure is joined
to the bottom cover with a hollow structure formed between the flat
portion or the curved portion of the reinforcing structure and the
flat portion of the bottom cover, and wherein the volume of the
hollow structure formed by joining the reinforcing structure to the
bottom cover is within a range of 55% or more and 95% or less of
the volume of the space.
17. The housing according to claim 16, wherein the projected area
of the reinforcing structure in a direction of the bottom cover
which is joined to the reinforcing structure is within a range of
60% or more and 95% or less of the area of the bottom cover to
which the reinforcing structure is joined.
18. The housing according to claim 17, wherein a shape of a
projected surface of the reinforcing structure is a rectangular
shape.
Description
TECHNICAL FIELD
The present invention relates to a housing such as a housing in
which an electronic device part is built (electronic device
housing), and a housing such as an attache case or a carry
case.
BACKGROUND ART
In recent years, for reducing the thickness and weight of an
electronic device, improving the portability of the electronic
device, and preventing breakage of components in the electronic
device, a housing has been required to have increased rigidity.
Specifically, when the electronic device is held with one hand and
operated with the other hand, when the electronic device is
transported, or when a monitor or the like is opened or closed, a
biased load is applied, and therefore a force acts on the housing
in a torsion direction. In addition, if the electronic device is
dropped by accident during transportation, a force also acts in a
torsion direction. Therefore, the housing is required to have high
torsional rigidity. In addition, when pressure is applied to a
housing at a cramped place such as a crowded train or when an
object is dropped (when a load is applied in a thickness
direction), an internal electronic component or a liquid crystal
component such as a display, particularly a glass member may be
damaged, and therefore the housing is required to have high
deflection rigidity. In view of such a background, many techniques
for increasing the rigidity of a housing have been heretofore
proposed.
Specifically, Patent Document 1 discloses an invention for
increasing the rigidity of an electric device cabinet structure
which includes a resin lower case having upper and lower electric
device mounting surfaces, and an upper case having a front wall
overlapping the upper electric device mounting surface. Patent
Document 2 discloses an invention for increasing the rigidity of an
electronic device housing by abutting the tip of a rib, which is
formed on the inner surface of a first housing, against the inner
surface of a second housing. Patent Document 3 discloses an
invention for increasing the rigidity of an electronic device
housing of by making the electronic device housing have a structure
in which surfaces of two plates are selectively bonded and joined
together.
In addition, in recent years, a housing has been more frequently
exposed to a high-temperature environment due to heat generation
associated with use in a high-temperature and high-humidity
environment and sophistication of specifications of electronic
components. Under such a high-temperature environment, for example,
it may be unable to operate buttons due to occurrence of warpage or
distortion, waterproofness may be deteriorated due to generation of
gaps, or rigidity may be reduced due to detachment of a reinforcing
structure, leading to impairment of functions inherent in an
electronic device when the housing is formed of different
materials. In view of such a background, many techniques for
improving the dimensional stability of the housing have been
proposed.
Specifically, Patent Document 4 discloses an invention for
improving the heat dissipation property of an information
processing apparatus including an outer housing to which a first
case and a second case are bonded, and a metal frame disposed in
the outer housing and attached to the outer housing. Patent
Document 3 discloses an invention for increasing the rigidity of an
electronic device housing of by making the electronic device
housing have a structure in which surfaces of two plates are
selectively bonded and joined together.
PRIOR ART DOCUMENTS
Patent Documents
Patent Document 1: Japanese Patent Laid-open Publication No.
10-150280 Patent Document 2: Japanese Patent Laid-open Publication
No. 2011-22848 Patent Document 3: Japanese Patent Laid-open
Publication No. 8-288681 Patent Document 4: Japanese Patent
Laid-open Publication No. 2007-305041
SUMMARY OF THE INVENTION
Problems to be Solved by the Invention
However, in the inventions disclosed in Patent Documents 1 and 2,
the housing is formed of a resin material, and therefore it is not
possible to provide a housing having a level of torsional rigidity
and deflection rigidity required in the market. In the inventions
disclosed in Patent Documents 1 and 2, it is also conceivable that
the housing is formed from a metal plate. However, in the
inventions disclosed in Patent Documents 1 and 2, the housing is
formed by joining or abutting members. Thus, even if the housing is
formed from a metal plate, it is not possible to provide a housing
having a level of torsional rigidity required in the market. In
addition, when the housing is formed from a metal plate, the weight
of the housing increases, and thus it is not possible to meet
market needs from the viewpoint of lightness.
In the invention disclosed in Patent Document 3, the rigidity of
the housing of an electronic device is increased by joining an
inner plate to the whole surface of an outer plate. However, the
inner plate is provided with a heat pipe channel by
stretch-molding, so that the thickness of the plate decreases, and
therefore torsional rigidity required for the housing cannot be
attained. In addition, a method in which an inner plate is joined
to the whole surface of an outer plate is not a method for
effectively improving rigidity from the viewpoint of lightness, and
it is not likely that a sufficient level of torsional rigidity is
obtained.
As described above, in conventional techniques for increasing the
rigidity of the housing, it is not possible to impart high
torsional rigidity and deflection rigidity to the housing while
attaining thickness reduction and weight reduction. Thus, it is
expected to provide a technique capable of imparting high torsional
rigidity and deflection rigidity to the housing while attaining
thickness reduction and weight reduction.
In addition, in conventional techniques for increasing the rigidity
of the housing, it is not possible to impart high torsional
rigidity to the housing while attaining thickness reduction, weight
reduction and improvement of portability. Thus, it is expected to
provide a technique capable of imparting high torsional rigidity to
the housing while attaining thickness reduction and weight
reduction.
In addition, in the invention disclosed in Patent Document 4, each
member is fixed by screws, and therefore when a fixed portion is
exposed to high heat as the information processing device is
operated, distortion occurs in each member, leading to impairment
of dimensional stability. Similarly, in the invention disclosed in
Patent Document 3, the surfaces of two plates are bonded to each
other, and therefore when a bonded portion is exposed to high heat
as the electronic device is operated, the bonded portion is
delaminated, leading to impairment of dimensional stability. Thus,
it is desired to provide a technique capable of imparting high
dimensional stability to the housing. In addition, fixed or joined
members serve to increase rigidity, and therefore if distortion or
delamination occurs, rigidity that should be properly exhibited
cannot be secured.
The present invention has been made in view of the above-described
problems, and an object of the present invention is to provide a
housing having improved torsional rigidity and deflection rigidity
while attaining thickness reduction and weight reduction.
Another object of the present invention is to provide a housing
having improved torsional rigidity while attaining thickness
reduction, weight reduction and improvement of portability.
Still another object of the present invention is to provide a
housing having high torsional rigidity and improved dimensional
stability.
Solutions to the Problems
A housing according to a first aspect of the present invention
includes: a top cover; a bottom cover having a rising wall member
erected toward the top cover and joined to the top cover at a rim;
and a reinforcing structure which is disposed in a space divided by
the top cover and the bottom cover, and has an opening, the
reinforcing structure being joined to the bottom cover, in which
the bottom cover being formed of a material having a thickness of
0.1 mm or more and 0.8 mm or less and an elastic modulus of 20 GPa
or more and 120 GPa or less.
A housing according to a second aspect of the present invention
includes: a top cover; a bottom cover having a rising wall member
erected toward the top cover and joined to the top cover at a rim;
and a reinforcing structure which is disposed in a space divided by
the top cover and the bottom cover, and has an opening, the
reinforcing structure being joined to the bottom cover, in which
the bottom cover is formed of a fiber-reinforced composite material
that is a cured product of a laminate of prepregs including a
reinforcing fiber and a matrix resin.
In the housings according to the first and second aspects of the
present invention, the reinforcing structure is formed of a
material having a thickness of 0.3 mm or more and 0.8 mm or less,
and an elastic modulus of 20 GPa or more and 120 GPa or less, in
the above-described invention.
A housing according to a third aspect of the present invention
includes: a top cover; a bottom cover having a rising wall member
erected toward the top cover and joined to the top cover at a rim;
and a reinforcing structure which is disposed in a space divided by
the top cover and the bottom cover, and has an opening, the
reinforcing structure being joined to the bottom cover, in which
the reinforcing structure is formed of a material having a
thickness of 0.3 mm or more and 0.8 mm or less and an elastic
modulus of 20 GPa or more and 120 GPa or less.
A housing according to a fourth aspect of the present invention
includes: a top cover; a bottom cover having a rising wall member
erected toward the top cover and joined to the top cover at a rim;
and a reinforcing structure which is disposed in a space divided by
the top cover and the bottom cover, and has an opening, the
reinforcing structure being joined to the bottom cover, in which
the reinforcing structure is formed of a fiber-reinforced composite
material that is a cured product of a laminate of prepregs
including a reinforcing fiber and a matrix resin.
In the housings according to the third and fourth aspects of the
present invention, the bottom cover is formed of a material having
a thickness of 0.1 mm or more and 0.8 mm or less, and an elastic
modulus of 20 GPa or more and 120 GPa or less, in the
above-described invention.
In the housings according to the first, second, third and fourth
aspects of the present invention, the reinforcing structure, and
the top cover or the bottom cover to which the reinforcing
structure is joined are formed of a fiber-reinforced composite
material that is a cured product of a laminate of prepregs
including a reinforcing fiber and a matrix resin, in the
above-described invention.
A housing according to a fifth aspect of the present invention
includes: a top cover; a bottom cover having a rising wall member
erected toward the top cover and joined to the top cover at a rim;
and a reinforcing structure which is disposed in a space divided by
the top cover and the bottom cover, and has an opening, the
reinforcing structure being joined to the bottom cover or the top
cover, in which a ratio of the linear expansion coefficient of the
reinforcing structure to the linear expansion coefficient of the
bottom cover or the top cover which is joined to the reinforcing
structure is within a range of 0.1 or more and 10 or less.
In the housings according to the first, second, third, fourth and
fifth aspects of the present invention, the reinforcing structure
is joined to the bottom cover or the top cover by thermal welding,
in the above-described invention.
In the housings according to the first, second, third, fourth and
fifth aspects of the present invention, the reinforcing structure
is joined to the bottom cover or the top cover in such a manner
that the peeling load at 23.degree. C. is within a range of 60
N/cm.sup.2 or more and 5000 N/cm.sup.2 or less, and the peeling
load at 200.degree. C. is within a range of less than 60
N/cm.sup.2, in the above-described invention.
In the housings according to the first, second, third, fourth and
fifth aspects of the present invention, the reinforcing structure
is joined directly to the top cover or the bottom cover, in the
above-described invention.
In the housings according to the first, second, third, fourth and
fifth aspects of the present invention, the projected area of the
reinforcing structure in a direction of the bottom cover or the top
cover which is joined to the reinforcing structure is within a
range of 60% or more and 95% or less of the area of the bottom
cover or the top cover to which the reinforcing structure is
joined, in the above-described invention.
In the housings according to the first, second, third, fourth and
fifth aspects of the present invention, the volume of a hollow
structure formed by joining the reinforcing structure to the bottom
cover or the top cover is within a range of 55% or more and 95% or
less of the volume of the space, in the above-described
invention.
In the housings according to the first, second, third, fourth and
fifth aspects of the present invention, the reinforcing structure
is joined to the bottom cover or the top cover to form a hollow
structure, and a heat generation member is disposed on a surface of
the reinforcing structure on the hollow structure side, in the
above-described invention.
In the housings according to the first, second, third, fourth and
fifth aspects of the present invention, another reinforcing
structure connecting the inner surface of the reinforcing structure
and the bottom cover to which the reinforcing structure is joined
is provided in a hollow structure formed between the reinforcing
structure and the bottom cover to which the reinforcing structure
is joined, in the above-described invention.
Effects of the Invention
In the housing according to the present invention, torsional
rigidity and deflection rigidity can be improved while thickness
reduction and weight reduction are attained. In addition, the
housing according to the present invention has improved torsional
rigidity while attaining thickness reduction, weight reduction and
improvement of portability. In addition, the housing according to
the present invention has high torsional rigidity and improved
dimensional stability.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view showing a configuration of a housing
according to one embodiment of the present invention.
FIG. 2 is an exploded perspective view of the housing shown in FIG.
1.
FIGS. 3(a) to 3(c) are sectional views showing one example of a
configuration of a reinforcing structure.
FIGS. 4(a) and 4(b) are sectional views showing one example of a
configuration of the reinforcing structure shown in FIG. 2.
FIGS. 5(a) and 5(b) are sectional views showing one example of a
configuration of the reinforcing structure shown in FIG. 2.
FIGS. 6(a) and 6(b) are sectional views showing one example of a
configuration of a housing.
FIGS. 7(a) and 7(b) show a plan view and a sectional view showing a
configuration of another reinforcing structure.
FIGS. 8(a) and 8(b) are schematic views for illustrating a
torsional rigidity test method.
FIG. 9 is a schematic view for illustrating a deflection rigidity
test method.
FIG. 10 is a schematic view for illustrating a peeling load test
method.
FIG. 11 is a schematic view showing a configuration of a
laminate.
FIGS. 12(a) and 12(b) are schematic views for illustrating a press
molding method.
FIGS. 13(a) and 13(b) are schematic views for illustrating a press
molding method.
FIG. 14 is a schematic view for illustrating a method for preparing
a housing.
FIG. 15 is a schematic view for illustrating a method for preparing
a housing.
EMBODIMENTS OF THE INVENTION
Hereinafter, a housing according to one embodiment of the present
invention will be described with reference to FIGS. 1 to 7.
Examples of the application of the housing of the present invention
may include attache cases, carry cases and electronic device
housings in which an electronic device component is built, and more
specific examples thereof include speakers, displays, HDDs,
notebook personal computers, mobile phones, digital still cameras,
PDAs, plasma displays, televisions, lighting systems, refrigerator
and game machines. In particular, the housing is preferably used
for clamshell-type personal computers and tablet-type personal
computers which have high torsional rigidity and are required to be
light and thin.
FIG. 1 is a perspective view showing a configuration of the housing
according to the first embodiment of the present invention. As
shown in FIG. 1, a housing 1 according to one embodiment of the
present invention includes, as main components, a bottom cover 2
rectangular in plan view, a reinforcing structure 3 joined to the
bottom cover 2 and having an opening, and a top cover 4 rectangular
in plan view. In the following description, a direction parallel to
short sides of the bottom cover 2 and the top cover 4 is defined as
an x direction, a direction parallel to long sides of the bottom
cover 2 and the top cover 4 is defined as a y direction, and a
direction perpendicular to the x direction and the y direction is
defined as a z direction (vertical direction).
FIG. 2 is an exploded perspective view of the housing 1 shown in
FIG. 1. As shown in FIG. 2, the bottom cover 2 includes a flat
portion 21 parallel to an x-y plane and rectangular in plan view,
and a rising wall member 22 erected in the positive direction of z
from a rim of the flat portion 21. The thickness of a member that
forms the bottom cover 2 is preferably within a range of 0.1 mm or
more and 0.8 mm or less. In addition, the elastic modulus of the
member that forms the bottom cover 2 is preferably within a range
of 20 GPa or more and 120 GPa or less.
In addition, it is preferable that the bottom cover 2 is formed of
any one of a metal material and a fiber-reinforced composite
material, and the bottom cover 2 may be formed by combining these
materials. From the viewpoint of exhibiting high torsional
rigidity, the bottom cover 2 is preferably a seamless member formed
of the same material. From the viewpoint of productivity, the flat
portion 21 having a simple shape may be formed using the metal
material and the fiber-reinforced composite material which have
high dynamic properties, and the rising wall member 22 and a
joining portion which have a complicated shape may be formed by
injection molding etc. using a resin material excellent in
moldability.
It is preferable to use a light metal material such as an aluminum
alloy, a magnesium alloy or a titanium alloy as the metal material.
Examples of the aluminum alloy may include A2017 and A2024 as
Al--Cu systems, A3003 and A3004 as Al--Mn systems, A4032 as an
Al--Si system, A5005, A5052 and A5083 as Al--Mg systems, A6061 and
A6063 as Al--Mg--Si systems, and A7075 as an Al--Zn system.
Examples of magnesium alloy may include AZ31, AZ61 and AZ91 as
Mg--Al--Zn systems. Examples of the titanium alloy may include
alloys containing palladium of grades 11 to 23, alloys containing
cobalt and palladium, and Ti-6Al-4V corresponding to grade 50
(.alpha. alloy), grade 60 (.alpha.-.beta. alloy) and grade 80
(.beta. alloy).
As reinforcing fibers to be used in the fiber-reinforced composite
material, fibers such as carbon fibers, glass fibers, aramid
fibers, boron fibers, PBO fibers, high strength polyethylene
fibers, alumina fibers and silicon carbide fibers can be used, and
two or more of these fibers may be mixed, and used. These
reinforcing fibers can be used as fiber structures such as long
fibers aligned in one direction, single tows, woven fabrics, knits,
nonwoven fabrics, mats and braided cords.
Examples of the matrix resin that can be used include thermosetting
resins such as epoxy resins, phenol resins, benzoxazine resins and
unsaturated polyester resins, polyester-based resins such as
polyethylene terephthalate (PET), polybutylene terephthalate (PBT),
polytrimethylene terephthalate (PTT), polyethylene naphthalate and
liquid crystal polyester, polyolefins such as polyethylene (PE),
polypropylene (PP) and polybutylene, styrene-based resins, urethane
resins, and thermosetting resins such as polyoxymethylene (POM),
polyamide (PA), polycarbonate (PC), polymethyl methacrylate (PMMA),
polyvinyl chloride (PVC), polyphenylene sulfide (PPS),
polyphenylene ether (PPE), modified PPE, polyimide (PI),
polyamideimide (PAI), polyether imide (PEI), polysulfone (PSU),
modified PSU, polyether sulfone (PES), polyketone (PK), polyether
ketone (PEK), polyether ether ketone (PEEK), polyether ketone
ketone (PEKK), polyarylate (PAR), polyether nitrile (PEN),
phenol-based resins, and phenoxy resins. From the viewpoint of
productivity and dynamic characteristics, thermosetting resins are
preferably used, and among them, epoxy resins are preferably used.
From the viewpoint of moldability, thermoplastic resins are
preferably used. Among them, polyamide resins are preferably used
from the viewpoint of strength, polycarbonate resins are preferably
used from the viewpoint of impact resistance, polypropylene resins
are preferably used from the viewpoint of lightness, and
polyphenylene sulfide resins are preferably used from the viewpoint
of heat resistance. The resin may be used not only as a matrix
resin of the fiber-reinforced composite material but also as the
bottom cover, the top cover or the reinforcing structure which is
composed of a resin itself.
In the present invention, it is preferable that a prepreg including
the reinforcing fiber and matrix resin is used as a material of
each member from the viewpoint of handling characteristics in
lamination etc. From the viewpoints of high dynamic characteristics
and design freedom, it is preferable to use unidirectional
continuous fiber prepreg, and from the viewpoint of isotropic
dynamic characteristics and moldability, it is preferable to use a
fabric prepreg. In addition, the member may be composed of a
laminate of these prepregs.
The reinforcing structure 3 is a member having an opening.
Specifically, the reinforcing structure 3 includes a flat portion
31 parallel to an x-y plane and rectangular in plan view, and a
rising wall member 32 erected in the negative direction of z from a
rim of the flat portion 31. A surface of the flat portion 31, which
faces the flat portion 21 of the bottom cover 2, may be packed with
an electronic device. The reinforcing structure 3 is joined to the
bottom cover 2 with a hollow structure S1 formed between the flat
portion 31 and the flat portion 21 of the bottom cover 2 by joining
the reinforcing structure 3 to the flat portion 21 of the bottom
cover 2. As used herein, the "reinforcing structure having an
opening" refers to a shape having an opening in apart of the
reinforcing structure, and may be a member having a flat portion, a
rising wall member and a surface connecting the flat portion and
the rising wall member as shown in FIGS. 3(a) and 3(b), or a member
having a curved surface. In addition, one example of the
reinforcing structure having an opening is a reinforcing structure
having a flat portion, a rising wall member erected on the rim of
the flat portion, and a joining portion extending from the rim of
the rising wall member as shown in FIG. 3(c), or having a curved
portion, and a joining portion extending from a rim of the
curved.
The area of the joining area in a plane parallel to the x-y plane
is preferably within a range of 10 cm.sup.2 or more and 100
cm.sup.2 or less. Specifically, when the joining area is less than
10 cm.sup.2, there arises the problem if a load that causes large
deformation is applied to the housing 1, the reinforcing structure
3 is peeled from the bottom cover 2, and thus original torsional
rigidity cannot be exhibited. On the other hand, when the joining
area is larger than 100 cm.sup.2, there arises the problem that the
increase in joining area causes an increase in weight of the
housing 1 and a decrease in volume of the hollow structure S1.
Thus, the joining area is preferably within a range of 10 cm.sup.2
or more and 100 cm.sup.2 or less.
The maximum value of a distance h between the flat portion 31 of
the reinforcing structure 3 and the flat portion 21 of the bottom
cover 2 (height of the reinforcing structure 3 from the flat
portion 21) is preferably within a range of 3 mm or more and 30 mm
or less. In the present invention, the height h of the reinforcing
structure 3 is one factor of exhibiting torsional rigidity. Thus,
when the maximum value of the height h is less than 3 mm, there
arises the problem that the effect of the rising wall member 32 is
low in the housing 1, so that original torsional rigidity cannot be
exhibited. On the other hand, when the maximum value of the height
h is larger than 30 mm, there arises the problem that it is
necessary to increase the thickness of the rising wall member 32,
resulting in an increase in weight of the housing 1. Thus, the
maximum value of the height h is preferably within a range of 3 mm
or more and 30 mm or less.
FIGS. 4 and 5 are sectional views showing one example of a
configuration of the reinforcing structure 3 shown in FIG. 2. The
joining portion 33 may be provided so as to extend in an outward
direction parallel to the x-y plane from the rim of the rising wall
member 32 as shown in FIG. 4(a). In addition, the joining portion
33 may be provided so as to extend in an inward direction parallel
to the x-y plane from the peripheral portion of the rising wall
member 32 as shown in FIG. 4(b). In addition, it is preferable that
the angle .alpha. of the rising wall member 32 with respect to the
flat portion 21 of the bottom cover 2 (or the joining portion 33 of
the reinforcing structure 3) is within a range of 45.degree. or
more and 135.degree. or less as shown in FIGS. 5(a) and 5(b). FIG.
5(a) shows a state in which the angle .alpha. of the rising wall
member 32 is an acute angle, and FIG. 5(b) shows a state in which
the angle .alpha. of the rising wall member 32 is an obtuse
angle.
FIG. 6 is a sectional view showing one example of a configuration
of the housing. As shown in FIGS. 6(a) and 6(b), heat generation
members D1 and D2 are disposed in the hollow structure S1 formed by
joining the reinforcing structure 3 and the bottom cover 2 or the
top cover 4. It is preferable that the heat generation members D1
and D2 are disposed on a surface of the reinforcing structure 3 on
the hollow structure S1 side. With this configuration, the distance
between the bottom cover 2 touched by a user of an electronic
device and the heat generation members D1 and D2 can be increased
to suppress elevation of the temperature of the bottom cover 2. In
this specification, the "heat generation member" means a component
that generates heat as an electronic device is operated, and
particularly refers to a component that causes temperature
elevation by 10.degree. C. or more as the electronic device is
operated. Examples of the heat generation member may include LEDs,
capacitors, inverters, reactor elements, thermistor elements, power
transistor elements, motors, CPUs, and electronic boards on which
these elements are mounted.
Deflection rigidity may also be increased by disposing another in
the hollow structure S1 formed between the flat portion 31 of the
reinforcing structure 3 and the flat portion 21 of the bottom cover
2. FIG. 7(a) is a plan view showing a configuration of another
reinforcing structure, and FIG. 7(b) is a sectional view taken
along line A-A in FIG. 7(a). As shown in FIGS. 7(a) and 7(b),
another reinforcing structure 5 is a member disposed so as to
extend in the x direction at the central part of the hollow
structure S1 in the y direction, and is connected to the flat
portion 21 of the bottom cover 2 and the flat portion 31 of the
reinforcing structure 3. By integrating the flat portion 21 of the
bottom cover 2 and the flat portion 31 of the reinforcing structure
3 with the other reinforcing structure 5 interposed therebetween,
the bottom cover 2 and the reinforcing structure 3 are deformed in
synchronization with each other if a load is applied, and therefore
the deflection rigidity of the housing 1 can be improved. In
addition, the rising wall member 22 of the bottom cover 2 and the
rising wall member 32 of the reinforcing structure 3 are integrated
with the other reinforcing structure 5, and thus the rising wall
members of the bottom cover 2 and the reinforcing structure 3 are
hardly deformed particularly inside direction of the housing 1, so
that the torsional rigidity of the housing 1 can be improved.
As long as the other reinforcing structure 5 is connected to the
flat portion 21 of the bottom cover 2 and the flat portion 31 of
the reinforcing structure 3, the other reinforcing structure 5 may
be a member disposed so as to extend in the y direction at the
central part of the hollow structure S1 in the x direction, or a
member disposed so as to extend in the diagonal direction of the
hollow structure S1. In particular, it is preferable that the other
reinforcing structure 5 is disposed so as to pass through a
position at which the amount of deflection of the flat portion 21
of the bottom cover 2 increases when a load is applied in the
thickness direction, and a plurality of members may be disposed
with the members crossing one another. In addition, it is
preferable that the other reinforcing structure 5 is formed of an
impact absorbing material excellent in elasticity, such as a resin
material having an elastomer or rubber component, or a gel, and
accordingly, not only deflection rigidity but also an effect
against impact can be exhibited.
In the present embodiment, a curved member may be used as the flat
portion 31, resulting in omission of the rising wall member 32. In
addition, from the viewpoint of increasing rigidity and effectively
utilizing the space, an irregular shape may be formed on the flat
portion 31. In the present embodiment, the reinforcing structure 3
is joined to the bottom cover 2, but the reinforcing structure 3
may be joined to the top cover 4 to form the hollow structure S1
between the flat portion 31 of the reinforcing structure 3 and the
top cover 4.
In the present embodiment, the joining portion 33 is formed on all
of the four rising wall members 32 formed on respective sides of
the flat portion 31, but the joining portion 33 may be formed on at
least one of the four rising wall members 32. Alternatively, the
joining portion 33 may be formed on two or more adjacent rising
wall members 32 among the four rising wall members 32. In addition,
the area of the joining portion 33 formed on one rising wall member
32 is preferably 1 cm.sup.2 or more. In addition, the thickness of
the member that forms the reinforcing structure 3 is preferably
within a range of 0.3 mm or more and 0.8 mm or less from the
viewpoint of reducing the weight and thickness of the housing. In
addition, the elastic modulus of the member that forms the
reinforcing structure 3 is preferably within a range of 20 GPa or
more and 120 GPa or less.
In addition, it is preferable that the reinforcing structure 3 is
formed of any one of the above-described metal material and
fiber-reinforced composite material, and the material can be
selected according to the purpose of the reinforcing structure 3.
That is, it is preferable to use a metal material or fiber
reinforced composite material having a high elastic modulus from
the viewpoint of exhibiting a high reinforcing effect, it is
preferable to use a metal material having a high thermal
conductivity from the viewpoint of heat dissipation, it is
preferable to use a non-conductive material such as a resin or a
glass fiber-reinforced composite material from the viewpoint of
exhibiting radio wave permeability (antenna property), and it is
preferable to use a conductive material such as a metal material or
a carbon fiber-reinforced composite material from the viewpoint of
exhibiting electromagnetic wave shielding property (radio wave
shielding property). Further, when the reinforcing structure 3 is
formed of a fiber-reinforced composite material, it is preferable
that the reinforcing structure 3 is composed of a laminate of
continuous fiber prepregs. In addition, the ratio of the linear
expansion coefficient of the reinforcing structure 3 to the linear
expansion coefficient of the bottom cover 2 to which the
reinforcing structure 3 is joined is preferably within a range of
0.1 or more and 10 or less.
In addition, it is preferable that the reinforcing structure 3 is
joined to the flat portion 21 of the bottom cover 2 by thermal
welding. The peeling load at 23.degree. C. is preferably within a
range of 60 N/cm.sup.2 or more and 5000 N/cm.sup.2 or less, more
preferably within a range of 100 N/cm.sup.2 or more and 5000
N/cm.sup.2 or less. Examples of the thermal welding method may
include an insert injection method, an outsert injection method, a
vibration welding method, an ultrasonic welding method, a laser
welding method and a hot plate welding method. Here, it is
preferable that the bonding surface between the reinforcing
structure 3 and the flat portion 21 has a peeling load of less than
60 N/cm.sup.2 at 200.degree. C. The peeling load at 200.degree. C.
is more preferably 30 N/cm.sup.2 or less.
In addition, this peeling load is preferably less than 60
N/cm.sup.2 at 180.degree. C., and it is preferable from the
viewpoint of disassembling adhesive that the peeling load can be
easily peeled off in a lower temperature range. However, when the
disassembling temperature lowers, the reinforcing structure may be
peeled off temperature elevation associated with operation of an
electronic component or depending on the temperature of a use
environment in use as a housing. Therefore, it is preferable that
in the temperature range where the housing is used, the reinforcing
structure is joined with high bonding strength, and in the
disassembling temperature range, the reinforcing structure can be
easily peeled off. Thus, the peeling load at 80.degree. C. is more
preferably within a range of 60 N/cm.sup.2 or more and 5000
N/cm.sup.2 or less.
The peeling load at 200.degree. C. is preferably as low as
possible, and most preferably 10 N/cm.sup.2 or less. Since the
peeling load at 200.degree. C. is preferably as low as possible,
the lower limit thereof is not particularly limited, and is
preferably 0 N/cm.sup.2 or more, but the peeling load at
200.degree. C. is more preferably 1 N/cm.sup.2 or more because when
it is excessively low, handling characteristics may be
deteriorated. With this configuration, disassembling bondability
that makes it possible to easily remove the reinforcing structure 3
can be exhibited, so that repair and recycling of an electronic
device can be facilitated. In addition, it is preferable that the
reinforcing structure 3, and the bottom cover 2 to which the
reinforcing structure 3 is joined are formed of a fiber-reinforced
composite material, a thermoplastic resin is provided in or on a
joining portion of at least one of the reinforcing structure 3 and
the bottom cover 2, and the reinforcing structure 3 and the bottom
cover 2 are joined with the thermoplastic resin, in the
above-described invention.
As a method for providing a thermoplastic resin on the joining
portion, mention is made of a method in which using a
fiber-reinforced sheet (prepreg sheet) including a thermoplastic
resin as a matrix resin, molding is performed to obtain the
reinforcing structure 3, and the bottom cover 2 or the top cover 4
to which the reinforcing structure 3 is joined. A molded product
obtained by this method is preferable because a thermoplastic resin
is present on a surface of the molded product at a high ratio, and
therefore it is possible to secure a wide bonding area in joining,
leading to an increase in selection freedom of a joining site. From
the viewpoint of the dynamic characteristics of the members, a
fiber-reinforced composite material including a thermosetting resin
as a matrix resin is preferable, and as a method for providing a
thermoplastic resin on such a member, a mention is made of a method
in which a molten material obtained by heating and melting a
thermoplastic resin or a solution obtained by dissolving a
thermoplastic resin in a solvent is applied to provide a
thermoplastic resin on the fiber-reinforced composite material. In
addition, a mention may be made of, for example, a method in which
in molding and curing of a fiber-reinforced sheet (prepreg sheet)
including a thermosetting resin as a matrix resin, a laminate in
which a film or nonwoven fabric composed of a thermoplastic resin
is laminated on a surface is molded under heat and pressure on the
outermost layer of the fiber-reinforced sheet (prepreg sheet).
In addition, it is preferable that the reinforcing structure 3 and
the bottom cover 2 or the top cover 4 are joined directly. When a
fiber-reinforced composite material having a thermoplastic resin is
used for the reinforcing structure 3 and/or the joining portion of
the bottom cover 2 or the top cover 4 that is bonded to the
reinforcing structure 3, it is not necessary to use an adhesive
agent other than the members, and the members can be joined
directly, so that an increase in weight of the housing 1 can be
suppressed. A suitable method for directly joining the reinforcing
structure 3 and the bottom cover 2 or the top cover 4 is a method
using a laminate, in which a film or nonwoven fabric composed of a
thermoplastic resin is laminated on a surface, for the outermost
layer of a fiber-reinforced sheet (prepreg sheet) including a
thermosetting resin as a matrix resin, and the thermoplastic resin
used here can also be selected from the group of thermoplastic
resins exemplified as the matrix resin.
Preferably, a thermoplastic resin is selected which has a melting
point lower than the molding temperature at which a
fiber-reinforced sheet (prepreg sheet) with the matrix resin
composed of a thermosetting resin is molded and cured. The lower
limit of the melting point of the thermoplastic resin is not
particularly limited, but it is preferably 80.degree. C. or higher,
more preferably 100.degree. C. or higher from the viewpoint of
exhibiting heat resistance in application of the housing of the
present invention to an electronic device. In addition, the form of
the thermoplastic resin is not particularly limited, and examples
thereof include forms of films, continuous fibers, woven fabrics,
particles, nonwoven fabrics and the like, but from the viewpoint of
handling characteristics during molding operation, forms of films
and nonwoven fabrics are preferable. By selecting such a resin, the
thermoplastic resin is melted during molding, and the thermoplastic
resin is formed while spreading like a film over a surface of a
molded product, so that the bonding area increases during joining,
or the reinforcing fibers of the fiber-reinforced sheet are
impregnated with the thermoplastic resin to form a strong
thermoplastic resin layer, so that high peeling strength can be
exhibited. The thermoplastic resin may be provided on at least one
of the reinforcing structure 3 obtained in the above-mentioned
method and the bottom cover 2 and the top cover 4 joined to the
reinforcing structure 3, but it is preferable that the
thermoplastic resin is provided on the joining members of both the
members to be joined. In addition, it is preferable that
substantially the same thermoplastic resin is selected as
thermoplastic resins to be provided.
In this specification, the "disassembling adhesive" means that the
reinforcing structure 3 can be not only easily removed, but also
re-bonded, and in re-bonding, the thermoplastic resin may be
provided, but it is preferable that the reinforcing structure can
be re-bonded without increasing the weight of the thermoplastic
resin or the like. In addition, the peeling load in re-bonding is
preferably 50% or more, more preferably 70% or more, of the
original peeling load. The disassembling adhesive in the present
invention can be attained by applying to a joining technique such
characteristics of a thermoplastic resin that the resin is melted
by heating to reduce dynamic characteristics, and the resin is
solidified by cooling or at normal temperature to exhibit high
dynamic characteristics specific to the resin.
In addition, a hole can be formed in each of the flat portion 31
and the rising wall member 32 of the reinforcing structure 3 to the
extent that torsional rigidity in the present invention is
improved. With such a structure, it is possible to dispose a wiring
cable for connecting an electronic component built in the hollow
structure S1 to an electronic component disposed in a space other
than the hollow structure S1 divided by the bottom cover 2 and the
top cover 4, and a display, a key board and so on which correspond
to the top cover 4. From the viewpoint of heat dissipation, it is
preferable that the hole is disposed to so as to improve the flow
of air, e.g. the hole is formed on the opposed rising wall member
32. The area of the holes is preferably 30% or less of the surface
area of the reinforcing structure 3, and is more desirably 15% or
less of the surface area of the reinforcing structure 3 from the
viewpoint of torsional rigidity.
The top cover 4 is joined to the rim of the rising wall member 22
of the bottom cover 2. In FIG. 1, the top cover 4 has a smooth
plate shape, but may have a plate shape having a curved surface or
irregularities. The material and shape of the top cover 4 may be
the same as those of the bottom cover 2, and a plurality of
reinforcing structures may be disposed and joined in a space by
dividing the reinforcing structure 3 by the bottom cover 2 and the
top cover 4. With such a configuration, the housing 1 having high
rigidity on either of surfaces thereof can be obtained. In
addition, the top cover 4 may be an electronic component such as a
liquid crystal display or a keyboard, and with such a
configuration, application to a clamshell-type personal computer or
a tablet-type personal computer is possible.
The hollow structure S1 may be formed by forming the reinforcing
structure 3 from a member having an opening, and joining the
reinforcing structure 3 to the bottom cover 2 or the top cover 4.
Here, it is preferable that the projected area of the reinforcing
structure 3 in a direction of the bottom cover 2 or top cover 4 to
which the reinforcing structure 3 is joined is adjusted to fall
within a range of 60% or more and 95% or less of the projected area
of the bottom cover 2 or top cover 4 to which the reinforcing
structure 3 is joined. The disposed position of the reinforcing
structure 3 is not particularly limited, but it is preferable that
the reinforcing structure 3 is positioned equally from the center
position C of the bottom cover 2 or the top cover 4, and by
disposing the reinforcing structure 3 in this manner, torsional
rigidity in an x direction or a y direction can be made isotropic.
From the viewpoint of effectively utilizing a space other than the
hollow structure S1, in the space divided by the bottom cover 2 and
the top cover 4, the reinforcing structure 3 may be placed on any
one of the bottom cover 2 or the top cover 4.
Specifically, when the projected area of the reinforcing structure
3 is less than 60% of the area of the bottom cover 2 or the top
cover 4 to which the reinforcing structure 3 is joined, there
arises the problem that the rising wall member that is one factor
of exhibiting torsional rigidity in the present invention is formed
at a position close to the center position of the bottom cover 2 or
the top cover 4, so that original torsional rigidity cannot be
exhibited. On the other hand, when the projected area of the
reinforcing structure 3 is more than 95% of the area of the bottom
cover 2 or the top cover 4 to which the reinforcing structure 3 is
joined, high torsional rigidity can be exhibited, but there arises
the problem that the space other than the hollow structure S1
becomes small, and therefore it is difficult to dispose electronic
components and wiring and the like for forming an electronic
device, so that application as a housing is difficult. Thus, the
projected area in a direction of the bottom cover 2 or top cover 4
to which the reinforcing structure 3 is joined is preferably within
a range of 60% or more and 95% or less of the area of the joined
bottom cover 2 or top cover 4 to which the reinforcing structure 3
is joined.
Here, the shape of the projected surface of the reinforcing
structure 3, i.e. the shape of the flat portion 31 is not
particularly limited, and may be not only a rectangular shape, but
also a circular shape or a polygonal shape, and from the viewpoint
of exhibiting high deflection rigidity, a shape conforming to the
shape of the bottom cover 2 and/or the top cover 4 is preferable.
Specifically, the shape of the projected surface of the reinforcing
structure 3 is preferably a rectangular shape. In addition, from
the viewpoint of effectively utilizing the hollow structure S1 and
a space other than the hollow structure S1, the shape of the
projected surface of the reinforcing structure 3 is preferably a
shape conforming to the shape of an electronic component to be
packed. In addition, from the viewpoint of exhibiting isotropic
rigidity against any load, the shape of the projected surface of
the reinforcing structure 3 is preferably a shape that is symmetric
with respect to an axis in the x direction and/or the y
direction.
In addition, when the hollow structure S1 is formed by forming the
reinforcing structure 3 from a member having the opening, and
joining the reinforcing structure 3 to the bottom cover 2 or the
top cover 4, the volume of the hollow structure S1 formed by the
reinforcing structure 3 in the bottom cover 2 is preferably within
a range of 55% or more and 95% or less of the volume of the space
divided by the bottom cover 2 and the top cover 4. Specifically,
when the volume of the hollow structure S1 is less than 55% of the
volume of the space divided by the bottom cover 2 and the top cover
4, there arises the problem that the height of the rising wall
member that is one factor exhibiting torsional rigidity in the
present invention is low and/or the projected area of the
reinforcing structure 3 is small, so that original torsional
rigidity cannot be exhibited. On the other hand, when the volume of
the hollow structure S1 is more than 95% of the volume of the space
divided by the bottom cover 2 and the top cover 4, high torsional
rigidity can be exhibited, but there arises the problem that the
space other than the hollow structure S1 becomes small, and thus it
is difficult to dispose electronic components and wiring and the
like for forming an electronic device, so that application as a
housing is difficult. Thus, the volume of the hollow structure S1
is preferably within a range of 55% or more and 95% or less of the
volume of the space divided by the bottom cover 2 and the top cover
4.
EXAMPLES
Hereinafter, first and second aspects of the present invention will
be described in detail by way of examples. However, the present
invention is not limited to the following examples.
<Evaluation and Measurement Methods>
(1) Torsional Rigidity Test
A housing 1 was fixed in a tester in such a manner that one side of
the housing 1 was fixed by a U-shaped fixing tool 100, and the
other side opposed to the fixed side was held by a support tool 101
as shown in FIG. 8(a), the displacement amount of the housing 1 was
then measured when a load of 50 N was applied with a change rate
set to 1.degree./min at an angle .theta. as shown in FIG. 8(b), and
the measured value was defined as a torsional rigidity value of the
housing.
(2) Deflection Rigidity Test
As shown in FIG. 9, the housing was installed in a tester in such a
manner that it was able to apply a load F from the side of a bottom
cover 2 or a top cover 4 to which a reinforcing structure was
joined. "Instron" (registered trademark) Universal Tester Model
4201 (manufactured by Instron Co., Ltd.) was used as a tester. The
deflection amount of the bottom cover 2 or the top cover 4 was
measured when a load of 100 N was applied with the housing 1
pressed at the center position at a cross head speed of 1.0 mm/min
using an indenter 102 having a diameter of 20 mm, and the measured
value was defined as a deflection rigidity value.
(3) Evaluation of Flexural Modulus
In accordance with the specifications in ASTM D-790 (1997), the
flexural moduli of materials to be used for the reinforcing
structure 3, the bottom cover 2 and the top cover 4 were evaluated.
From each of members obtained in examples and comparative examples,
a bending test piece having a width of 25.+-.0.2 mm with a length
set to span L+20.+-.1 mm so that the thickness D and the span L
satisfied the relationship of L/D=16 was cut for the four
directions: 0.degree., +45.degree., -45.degree. and 90.degree.
directions where a certain direction was set to the 0.degree.
direction. In this way, test pieces were prepared. The number of
measurements (n) in each direction was 5, and the average value of
all measured values (n=20) was defined as a flexural modulus.
"Instron" (registered trademark) Universal Tester Model 4201
(manufactured by Instron Co., Ltd.) was used as a tester, a
three-point bending test tool (indenter diameter: 10 mm, fulcrum
diameter: 10 mm) was used, the support span was set to 16 times of
the thickness of the test piece, and the bending elastic modulus
was measured. The test was conducted under the following
conditions: the moisture content of the test piece was 0.1 mass %
or less, the atmospheric temperature was 23.degree. C., and the
humidity was 50% by mass.
(4) Peeling Load Test of Reinforcing Structure (23.degree. C. and
200.degree. C.)
The peeling load of the reinforcing structure was evaluated in
accordance with "Testing methods for tensile strength of adhesive
bonds" specified in JIS K6849 (1994). As test pieces in this test,
housings obtained in examples and comparative examples were used.
Here, for measuring the peeling strength of the reinforcing
structure, evaluation was performed in a state in which there was
not a top cover or bottom cover to which the reinforcing structure
was not joined (before the reinforcing structure was joined).
Specifically, as shown in FIG. 10, the bottom cover 2 or the top
cover 4 of the housing 1 was fixed by a fixing tool 103, and the
reinforcing structure 3 was fixed by a tensile tool 104. A tensile
load F was applied while each member was fixed, and evaluation was
performed until the reinforcing structure 3 was peeled off, or the
tensile tool 104 was detached from the reinforcing structure 3. The
bonding area here was calculated by measuring the width and length
of the joining surface of the reinforcing structure 3 before
joining. When joining was partially performed, the areas thereof
were measured, and summed to determine a joining area. The peeling
load of the reinforcing structure 3 was calculated from the
resulting tensile load value and joining area. For the peeling load
of the reinforcing structure 3 at 200.degree. C., the housing 1 was
placed in a thermostat together with the fixing tool, and the
atmospheric temperature in the thermostat was elevated to
200.degree. C. After elevation of the temperature, this state was
maintained for 10 minutes, and a tensile load was then applied in
the same manner as in the peeling load test of the reinforcing
structure 3, and evaluation was performed.
<Materials Used>
Materials used for evaluation are shown below.
[Material 1]
"TORAYCA" Prepreg P3252S-12 (manufactured by Toray Industries,
Inc.) was provided as material 1. The properties of material 1 are
shown in Table 1 below.
[Material 2]
SCF 183 EP-BL 3 manufactured by Super Resin Industry Co., Ltd. was
provided as material 2. The properties of material 2 are shown in
Table 1 below.
[Material 3]
An aluminum alloy A5052 was provided as material 3. The properties
of material 3 are shown in Table 1 below.
[Material 4]
A magnesium alloy AZ31 was provided as material 4. The properties
of material 4 are shown in Table 1 below.
[Material 5]
Using a master batch including 90% by mass of a polyamide 6 resin
("AMILAN" (registered trademark) CM1021T manufactured by Toray
Industries, Inc.) and 10% by mass of a polyamide terpolymer resin
composed of polyamide 6/66/610 ("AMILAN" (registered trademark)
CM4000 manufactured by Toray Industries, Inc.), a thermoplastic
resin film having a basis weight of 124 g/m.sup.2 was prepared, and
provided as material 5. The properties of material 5 are shown in
Table 1 below.
TABLE-US-00001 TABLE 1 Mate- Mate- Mate- Mate- rial 1 rial 2 rial 3
rial 4 Material 5 Material -- CFRP GFRP Al Mg Ny resin alloy alloy
Elastic GPa 60 25 70 45 3.5 modulus Linear 10.sup.-6/.degree. C.
0.3 7 23.6 26 83 expansion coefficient Thermal W/m K 3.0 0.3 236.0
159.0 0.3 conductivity
Example 1
Example 1-(1): Preparation of Bottom Cover
Seven sheets having a predetermined size were cut from material 1.
Among them, four sheets were cut in such a manner that the fiber
direction of a prepreg was parallel to a longitudinal direction (x
direction in FIG. 1), and the other three sheets were cut in such a
manner that the fiber direction was parallel to a lateral direction
(y direction in FIG. 1). In this example, the lateral direction (y
direction) was set to 0.degree., and as shown in FIG. 11, a
laminate including seven prepreg sheets was prepared in such a
manner that prepreg sheets 105a with the fiber direction set to
90.degree. and prepreg sheets 105b with the fiber direction set to
0.degree. were symmetrically laminated.
Here, a press molding apparatus and a pair of molds 106 as shown in
FIG. 12(a) were used, and the resulting laminate 107 was disposed
in a pair of molds 106. Here, the heating platen temperature of the
press molding apparatus was set to 150.degree. C., and as shown in
FIG. 12(b), the molds 106 were moved, and the laminate was
pressurized with the molding pressure kept at 1.0 MPa. After 30
minutes, the molds 106 were opened, and the molded article was
removed from the molds 106. Trimming was performed in conformity to
the height of the resulting molded article to obtain a bottom
cover.
Example 1-(2): Preparation of Top Cover
Except that molds configured to prepare a molded article having a
smooth shape were used, the same procedure as in Example 1-(1) was
carried out to obtain a molded article. Trimming was performed so
that the resulting molded article had a desired size, thereby
obtaining a top cover.
Example 1-(3): Preparation of Reinforcing Structure
Except that molds 106 as shown in FIG. 13 were used, the same
procedure as in Example 1-(1) was carried out to obtain a molded
article. Trimming was performed so that the joining surface of the
resulting molded article had a desired width, thereby obtaining a
reinforcing structure.
Example 1-(4): Preparation of Housing
The members obtained in Examples 1-(1) to 1-(3) were joined using
an adhesive 108 as shown in FIG. 14. The molding conditions and
evaluation results in Example 1 are shown in Table 2 below.
Example 2
Except that a bottom cover having a size as described in Table 2
was molded and used, the same procedure as in Examples 1-(1) to
1-(4) was carried out to obtain a housing. The molding conditions
and evaluation results in Example 2 are shown in Table 2 below.
Example 3
Except that as the bottom cover, a material as described in Table 2
was used, the heating platen temperature was 220.degree. C., and
the molding pressure was 10 MPa, the same procedure as in Examples
1-(1) to 1-(4) was carried out to obtain a housing. The molding
conditions and evaluation results in Example 3 are shown in Table 2
below.
Example 4
Except that as the bottom cover, a material as described in Table 2
was used, the heating platen temperature was 200.degree. C., and
the molding pressure was 10 MPa, the same procedure as in Examples
1-(1) to 1-(4) was carried out to obtain a housing. The molding
conditions and evaluation results in Example 4 are shown in Table 2
below.
Example 5
Except that a bottom cover with a material as described in Table 3
was molded and used, the same procedure as in Examples 1-(1) to
1-(4) was carried out to obtain a housing. The molding conditions
and evaluation results in Example 5 are shown in Table 3 below.
Example 6
Except that a reinforcing structure with a material as described in
Table 3 was molded and used, the same procedure as in Examples
1-(1) to 1-(4) was carried out to obtain a housing. The molding
conditions and evaluation results in Example 6 are shown in Table 3
below.
Example 7
As another reinforcing structure, 25 sheets of material 1 were
laminated so as to have a thickness of 3 mm with 0.degree. prepreg
sheets and 90.degree. prepreg sheets being symmetrically laminated
in an alternate manner. In the same manner as in Example 1-(1), the
laminate was heated and pressurized by a press molding apparatus to
obtain a molded article. The resulting molded article was processed
so as to have a width of 7.2 mm, thereby obtaining another
reinforcing structure having a size as shown in Table 3. The
resulting another reinforcing structure was disposed as shown in
FIG. 7, and joined by an adhesive, and subsequently the same
procedure as in Examples 1-(1) to 1-(4) to obtain a housing. The
molding conditions and evaluation results in Example 7 are shown in
Table 3 below.
Example 8
Except that a reinforcing structure having a size as described in
Table 3 was molded and used, the same procedure as in Examples
1-(1) to 1-(4) was carried out to obtain a housing. The molding
conditions and evaluation results in Example 8 are shown in Table 3
below.
Example 9
A bottom cover and a reinforcing structure that were obtained in
the same manner as in Examples 1-(1) and 1-(3) were joined to each
other in the following manner: a molten hot melt resin (HM712
manufactured by Cemedine Co., Ltd.) was applied to a joining
portion of the reinforcing structure by a hot melt applicator at
140.degree. C., a reinforcing structure was superposed thereon, a
weight was placed on the reinforcing structure, and this state was
kept for 3 minutes. Except for the method for joining, the same
procedure as in Examples 1-(1) to 1-(4) was carried out to obtain a
housing. The molding conditions and evaluation results in Example 9
are shown in Table 4 below.
Example 10
Example 10-(1): Preparation of Bottom Cover
A film composed of a polyamide copolymer ("AMILAN" (registered
trademark) CM8000 manufactured by Toray Industries, Inc.) and
having a thickness of 50 .mu.m was laminated on a surface to be
joined to the reinforcing structure, thereby obtaining a laminate.
Except that the resulting laminate was used, the same procedure as
in Example 1-(1) was carried out to obtain a bottom cover.
Example 10-(2): Preparation of Top Cover
As in the case of Example 10-(1), a film composed of a polyamide
copolymer ("AMILAN" (registered trademark) CM8000 manufactured by
Toray Industries, Inc.) and having a thickness of 50 .mu.m was
laminated on a surface to be joined to the bottom cover, thereby
obtaining a laminate. Except that the resulting laminate was used,
the same procedure as in Example 1-(2) was carried out to obtain a
top cover.
Example 10-(3): Preparation of Reinforcing Structure
As in the case of Example 10-(1), a film composed of a polyamide
copolymer ("AMILAN" (registered trademark) CM8000 manufactured by
Toray Industries, Inc.) and having a thickness of 50 .mu.m was
laminated on a surface to be joined to the bottom cover, thereby
obtaining a laminate. Except that the resulting laminate was used,
the same procedure as in Example 1-(3) was carried out to obtain a
reinforcing structure.
Example 10-(4): Preparation of Housing
The reinforcing structure obtained in Example 10-(3) and the bottom
cover obtained in Example 10-(1) were superposed on each other in
joined form, a joining tool 109 as shown in FIG. 15 was provided,
and the joined bottom cover and reinforcing structure were
disposed, and heated and pressurized in a press molding apparatus
set so that the joining tool 109 had a surface temperature of
180.degree. C. After 1 minute, the bottom cover 2, the reinforcing
structure 3 and the joining tool 109 were taken out from the press
molding apparatus, and cooled. After 5 minutes, the joining tool
109 was removed to obtain an integrated product of the bottom cover
2 and the reinforcing structure 3. Thereafter, the same procedure
as in Example 1-(4) was carried out to obtain a housing. The
molding conditions and evaluation results in Example 10 are shown
in Table 4 below.
Example 11
Except that a reinforcing structure having a size as described in
Table 4 was molded and used, the same procedure as in Example 10
was carried out to obtain a housing. The molding conditions and
evaluation results in Example 11 are shown in Table 4 below.
Examples 12 to 14
Except that a reinforcing structure having a size as in Tables 4
and 5 was molded and used, the same procedure as in Example 10 was
carried out to obtain a housing. The molding conditions and
evaluation results in Examples 12 to 14 are shown in Tables 4 and 5
below.
Reference Example 1
Except that a size as described in Table 5 was employed, the same
procedure as in Example 12 was carried out to obtain a bottom cover
and a reinforcing structure. Electronic components were disposed in
a hollow structure S1 formed by the bottom cover and the
reinforcing structure, and a joining portion was joined by an
ultrasonic welding machine in the same manner as in Example 12. In
addition, as a top cover, a liquid crystal display was provided,
and joined to a bottom cover by a double-sided tape. The molding
conditions and evaluation results for the electronic device housing
obtained in Reference Example 1 are shown in Table 5 below.
Comparative Example 1
Except that a reinforcing structure was not used, the same
procedure as in Examples 1-(1) to 1-(4) was carried out to obtain a
housing. The molding conditions and evaluation results in
Comparative Example 1 are shown in Table 6 below.
Comparative Example 2
Except that a laminate obtained by laminating material 1 and
material 2 was used as a material of a bottom cover, the same
procedure as in Comparative Example 1 was carried out to obtain a
housing. The molding conditions and evaluation results in
Comparative Example 2 are shown in Table 6 below.
Comparative Example 3
Comparative Example 3-(1): Preparation of Bottom Cover
A laminate obtained by laminating 10 sheets of material described
in Table 6, a press molding apparatus, and a pair of molds 106 as
shown in FIG. 12(a) were used. The laminate was disposed in a pair
of molds 106. Here, the heating platen temperature of the press
molding machine was set to 260.degree. C., and the laminate was
pressurized with the molding pressure kept at 1.0 MPa. After 10
minutes, cooling water was made to pass through the heating plate,
so that cooling was started. After the mold temperature decreased
to 100.degree. C. or lower, the molds 106 were opened, and a molded
article was taken out from the molds 106. Trimming was performed so
that the rising wall of the resulting molded article had a desired
height, thereby obtaining a bottom cover.
Comparative Example 3-(2): Preparation of Reinforcing Structure and
Top Cover
Except that the mold to be used was changed so as to attain a size
as described in Table 6, the same procedure as in Comparative
Example 3-(1) was carried out to obtain a reinforcing structure and
a top cover.
Comparative Example 3-(3): Preparation of Housing
Except that the resulting bottom cover and reinforcing structure
were used, the same procedure as in Example 1-(4) was carried out
to join a bottom cover using an adhesive. The molding conditions
and evaluation results in Comparative Example 3 are shown in Table
6 below.
[Evaluation]
The housings obtained in examples were confirmed to exhibit high
torsional rigidity and deflection rigidity. Among them, the housing
of Example 1 exhibited very high torsional rigidity, and was also
capable of mounting many electronic devices etc. in a hollow
structure because the ratio of the hollow structure was high. It
was confirmed that in Example 7, not only torsional rigidity but
also further high deflection rigidity was exhibited due to the
effect of another reinforcing structure. Examples 9 to 11 are
preferable from the viewpoint of repair and recycling because the
bottom cover and the reinforcing structure are joined to each other
by heat welding, and therefore the joining portion can be
disassembled by thermal while high torsional rigidity and
deflection rigidity are exhibited. Examples 10 and 11 are
preferable from the viewpoint of weight reduction because the
reinforcing structure and the bottom cover are bonded directly to
each other, and therefore an increase in weight is smaller as
compared to a case where an adhesive or a hot melt resin is
used.
In Examples 3 and 4, not only high torsional rigidity but also
deflection rigidity was exhibited by using a metal material having
high dynamic properties for the bottom cover. In addition, the
metal material has a high thermal conductivity, and is therefore
preferable from the viewpoint of thermal characteristics. Example 5
is preferable from the viewpoint of not only high torsional
rigidity but also enabling radio wave communication because a
non-conductive material having electromagnetic wave permeability is
used for the bottom cover. Example 2 is intended to reduce the
thickness of the bottom cover, and thus contributes to weight
reduction and thickness reduction of the housing while maintaining
torsional rigidity. In addition, Reference Example 1 was provided
as a method for using a housing, where electronic components were
disposed in a hollow structure to prepare an electronic device with
a liquid crystal display used as atop cover. It was confirmed that
when the requirements of the present invention were satisfied, it
was possible to provide an electronic device exhibiting high
torsional rigidity and deflection rigidity.
On the other hand, the housings of Comparative Examples 1 and 2 had
very low resistance to torsion, so that there was the possibility
of damaging internal electronic components. In Comparative Example
3, a reinforcing structure was used, but a resin material was used
for each member, resulting in poor deflection rigidity.
TABLE-US-00002 TABLE 2 Example 1 Example 2 Example 3 Example 4
Bottom cover: Material -- Material 1 Material 1 Material 3 Material
4 Length mm 210 210 210 210 Width mm 300 300 300 300 Height mm 10
10 10 10 Thickness mm 0.8 0.4 0.6 0.8 Projected area cm.sup.2 630
630 630 630 Volume cm.sup.3 572 601 586 572 Top cover: Material --
Material 1 Material 1 Material 1 Material 1 Length mm 210 210 210
210 Width mm 300 300 300 300 Height mm -- -- -- -- Thickness mm 0.8
0.8 0.8 0.8 Projected area cm.sup.2 630 630 630 630 Volume cm.sup.3
-- -- -- -- Reinforcing structure: Material -- Material 2 Material
2 Material 2 Material 2 Length mm 200 200 200 200 Width mm 290 290
290 290 Height mm 8 8 8 8 Angle .degree. 90 90 90 90 Thickness mm
0.8 0.8 0.8 0.8 Overlap width mm 5 5 5 5 Bonding area cm.sup.2 48
48 48 48 Projected area cm.sup.2 580 580 580 580 Volume cm.sup.3
412 412 412 412 Another reinforcing structure Material -- -- -- --
-- Length mm -- -- -- -- Width mm -- -- -- -- Height mm -- -- -- --
Electronic device housing Projected area % 92.1 92.1 92.1 92.1
ratio Volume ratio % 72.0 68.6 70.2 72.0 Integration -- Adhesive
Adhesive Adhesive Adhesive method Bonding -- Plane Plane Plane
Plane portion Peeling load N/cm.sup.2 1500 1500 1500 1500
(23.degree. C.) Peeling load N/cm.sup.2 700 700 700 700
(200.degree. C.) Evaluation Torsional -- .circle-w/dot.
.circle-w/dot. .circle-w/dot. .largecircle. rigidity Deflection --
.largecircle. .largecircle. .largecircle. .largecircle.
rigidity
TABLE-US-00003 TABLE 3 Example 5 Example 6 Example 7 Example 8
Bottom cover: Material -- Material 2 Material 1 Material 1 Material
1 Length mm 210 210 210 210 Width mm 300 300 300 300 Height mm 10
10 10 10 Thickness mm 0.8 0.8 0.8 0.8 Projected area cm.sup.2 630
630 630 630 Volume cm.sup.3 572 572 572 572 Top cover: Material --
Material 1 Material 1 Material 1 Material 1 Length mm 210 210 210
210 Width mm 300 300 300 300 Height mm -- -- -- -- Thickness mm 0.8
0.8 0.8 0.8 Projected area cm.sup.2 630 630 630 630 Volume cm.sup.3
-- -- -- -- Reinforcing structure: Material -- Material 2 Material
1 Material 2 Material 2 Length mm 200 200 200 200 Width mm 290 290
290 290 Height mm 8 8 8 8 Angle .degree. 90 90 90 45 Thickness mm
0.8 0.8 0.8 0.8 Overlap width mm 5 5 5 5 Bonding area cm.sup.2 48
48 48 48 Projected area cm.sup.2 580 580 580 580 Volume cm.sup.3
412 412 412 412 Another reinforcing structure Material -- -- --
Material 1 -- Length mm -- -- 188 -- Width mm -- -- 3 -- Height mm
-- -- 4 -- Electronic device housing Projected area % 92.1 92.1
92.1 92.1 ratio Volume ratio % 72.0 72.0 72.0 72.0 Integration --
Adhesive Adhesive Adhesive Adhesive method Bonding -- Plane Plane
Plane Plane portion Peeling load N/cm.sup.2 1500 1500 1500 1500
(23.degree. C.) Peeling load N/cm.sup.2 700 700 700 700
(200.degree. C.) Evaluation Torsional -- .circle-w/dot.
.circle-w/dot. .circle-w/dot. .largecircle. rigidity Deflection --
.largecircle. .largecircle. .largecircle. .largecircle.
rigidity
TABLE-US-00004 TABLE 4 Example Example Example Example 9 10 11 12
Bottom cover: Material -- Material 1 Material 1 Material 1 Material
1 Length mm 210 210 210 210 Width mm 300 300 300 300 Height mm 10
10 10 10 Thickness mm 0.8 0.8 0.8 0.8 Projected area cm.sup.2 630
630 630 630 Volume cm.sup.3 572 572 572 572 Top cover: Material --
Material 1 Material 1 Material 1 Material 1 Length mm 210 210 210
210 Width mm 300 300 300 300 Height mm -- -- -- -- Thickness mm 0.8
0.8 0.8 0.8 Projected area cm.sup.2 630 630 630 630 Volume cm.sup.3
-- -- -- -- Reinforcing structure: Material -- Material 2 Material
2 Material 2 Material 2 Length mm 200 200 200 200 Width mm 290 290
290 290 Height mm 8 8 8 2 Angle .degree. 90 90 45 90 Thickness mm
0.8 0.8 0.8 0.8 Overlap width mm 5 5 5 5 Bonding area cm.sup.2 48
48 48 48 Projected area cm.sup.2 580 580 580 580 Volume cm.sup.3
412 412 412 69 Another reinforcing structure Material -- -- -- --
-- Length mm -- -- -- -- Width mm -- -- -- -- Height mm -- -- -- --
Electronic device housing Projected area % 92.1 92.1 92.1 92.1
ratio Volume ratio % 72.0 72.0 72.0 12.0 Integration -- Thermal
Thermal Thermal Thermal method welding welding welding welding
Bonding -- Plane Plane Plane Plane portion Peeling load N/cm.sup.2
2000 2500 2500 2500 (23.degree. C.) Peeling load N/cm.sup.2 50 50
50 50 (200.degree. C.) Evaluation Torsional -- .circle-w/dot.
.circle-w/dot. .largecircle. .largecircle. rigidity Deflection --
.largecircle. .largecircle. .largecircle. .largecircle.
rigidity
TABLE-US-00005 TABLE 5 Reference Example 13 Example 14 Example 1
Bottom cover: Material -- Material 1 Material 1 Material 1 Length
mm 210 210 180 Width mm 300 300 230 Height mm 10 10 7 Thickness mm
0.8 0.8 0.8 Projected area cm.sup.2 630 630 414 Volume cm.sup.3 572
572 253 Top cover: Material -- Material 1 Material 1 Display Length
mm 210 210 210 Width mm 300 300 300 Height mm -- -- -- Thickness mm
0.8 0.8 0.8 Projected area cm.sup.2 630 630 630 Volume cm.sup.3 --
-- -- Reinforcing structure: Material -- Material 2 Material 2
Material 2 Length mm 200 206 162 Width mm 290 296 215 Height mm 3 8
5 Angle .degree. 90 90 90 Thickness mm 0.8 0.8 0.5 Overlap width mm
5 5 5 Bonding area cm.sup.2 48 49 37 Projected area cm.sup.2 580
610 348 Volume cm.sup.3 126 433 155 Another reinforcing structure
Material -- -- -- -- Length mm -- -- -- Width mm -- -- -- Height mm
-- -- -- Electronic device housing Projected area % 92.1 96.8 84.1
ratio Volume ratio % 22.0 75.7 61.4 Integration -- Thermal Thermal
Thermal method welding welding welding Bonding portion -- Plane
Plane Plane Peeling load N/cm.sup.2 2500 2500 2500 (23.degree. C.)
Peeling load N/cm.sup.2 50 50 50 (200.degree. C.) Evaluation
Torsional -- .largecircle. .circle-w/dot. .circle-w/dot. rigidity
Deflection -- .largecircle. .largecircle. .largecircle.
rigidity
TABLE-US-00006 TABLE 6 Comparative Comparative Comparative Example
1 Example 2 Example 3 Bottom cover: Material -- Material 1 Material
1/ Material 5 Material 2 Length mm 210 210 210 Width mm 300 300 300
Height mm 10 10 10 Thickness mm 0.8 1.6 0.8 Projected area cm.sup.2
630 630 630 Volume cm.sup.3 572 516 572 Top cover: Material --
Material 1 Material 1 Material 5 Length mm 210 210 210 Width mm 300
300 300 Height mm -- -- -- Thickness mm 0.8 0.8 0.8 Projected area
cm.sup.2 630 630 630 Volume cm.sup.3 -- -- -- Reinforcing
structure: Material -- -- -- Material 5 Length mm -- -- 200 Width
mm -- -- 290 Height mm -- -- 8 Angle .degree. -- -- 90 Thickness mm
-- -- 0.8 Overlap width mm -- -- 5 Bonding area cm.sup.2 -- -- 48
Projected area cm.sup.2 -- -- 580 Volume cm.sup.3 -- -- 412 Another
reinforcing structure Material -- -- -- -- Length mm -- -- -- Width
mm -- -- -- Height mm -- -- -- Electronic device housing Projected
area % 0.0 0.0 92.1 ratio Volume ratio % 0.0 0.0 72.0 Integration
-- -- -- Adhesive method Bonding portion -- -- -- Plane Peeling
load N/cm.sup.2 -- -- 1500 (23.degree. C.) Peeling load N/cm.sup.2
-- -- 50 (200.degree. C.) Evaluation Torsional -- X X .largecircle.
rigidity Deflection -- X .largecircle. .DELTA. rigidity
Hereinafter, third and fourth aspects of the present invention will
be described in detail by way of examples. However, the present
invention is not limited to the following examples.
<Evaluation and Measurement Methods>
(1) Torsional Rigidity Test
A housing 1 was fixed in a tester in such a manner that one side of
the housing 1 was fixed by a U-shaped fixing tool 100, and the
other side opposed to the fixed side was held by a support tool 101
as shown in FIG. 8(a), the displacement amount of the housing 1 was
then measured when a load of 10 N was applied with a change rate
set to 1.degree./min at an angle .theta. as shown in FIG. 8(b), and
the measured value was defined as a torsional rigidity value of the
housing.
(2) Deflection Rigidity Test
As shown in FIG. 9, the housing was installed in a tester in such a
manner that it was able to apply a load F from the side of a bottom
cover 2 or a top cover 4 to which a reinforcing structure was
joined. "Instron" (registered trademark) Universal Tester Model
4201 (manufactured by Instron Co., Ltd.) was used as a tester. The
deflection amount of the bottom cover 2 or the top cover 4 was
measured when a load of 100 N was applied with the housing 1
pressed at the center position at a cross head speed of 1.0 mm/min
using an indenter 102 having a diameter of 20 mm, and the measured
value was defined as a deflection rigidity value.
(3) Evaluation of Flexural Modulus
In accordance with the specifications in ASTM D-790 (1997), the
flexural moduli of materials to be used for the reinforcing
structure 3, the bottom cover 2 and the top cover 4 were evaluated.
From each of members obtained in examples and comparative examples,
a bending test piece having a width of 25.+-.0.2 mm with a length
set to span L+20.+-.1 mm so that the thickness D and the span L
satisfied the relationship of L/D=16 was cut for the four
directions: 0.degree., +45.degree., -45.degree. and 90.degree.
directions where a certain direction was set to the 0.degree.
direction. In this way, test pieces were prepared. The number of
measurements (n) in each direction was 5, and the average value of
all measured values (n=20) was defined as a flexural modulus.
"Instron" (registered trademark) Universal Tester Model 4201
(manufactured by Instron Co., Ltd.) was used as a tester, a
three-point bending test tool (indenter diameter: 10 mm, fulcrum
diameter: 10 mm) was used, the support span was set to 16 times of
the thickness of the test piece, and the bending elastic modulus
was measured. The test was conducted under the following
conditions: the moisture content of the test piece was 0.1 mass %
or less, the atmospheric temperature was 23.degree. C., and the
humidity was 50% by mass.
(4) Peeling Load Test of Reinforcing Structure (23.degree. C. and
200.degree. C.)
The peeling load of the reinforcing structure was evaluated in
accordance with "Testing methods for tensile strength of adhesive
bonds" specified in JIS K6849 (1994). As test pieces in this test,
housings obtained in examples and comparative examples were used.
Here, for measuring the peeling strength of the reinforcing
structure, evaluation was performed in a state in which there was
not a top cover or bottom cover to which the reinforcing structure
was not joined (before the reinforcing structure was joined).
Specifically, as shown in FIG. 10, the bottom cover 2 or the top
cover 4 of the housing 1 was fixed by a fixing tool 103, and the
reinforcing structure 3 was fixed by a tensile tool 104. A tensile
load F was applied while each member was fixed, and evaluation was
performed until the reinforcing structure 3 was peeled off, or the
tensile tool 104 was detached from the reinforcing structure 3. The
bonding area here was calculated by measuring the width and length
of the joining surface of the reinforcing structure 3 before
joining. When joining was partially performed, the areas thereof
were measured, and summed to determine a joining area. The peeling
load of the reinforcing structure 3 was calculated from the
resulting tensile load value and joining area. For the peeling load
of the reinforcing structure 3 at 200.degree. C., the housing 1 was
placed in a thermostat together with the fixing tool, and the
atmospheric temperature in the thermostat was elevated to
200.degree. C. After elevation of the temperature, this state was
maintained for 10 minutes, and a tensile load was then applied in
the same manner as in the peeling load test of the reinforcing
structure 3, and evaluation was performed.
<Materials Used>
Materials used for evaluation are shown below.
[Material 11]
"TORAYCA" Prepreg P3252S-12 (manufactured by Toray Industries,
Inc.) was provided as material 11. The properties of material 11
are shown in Table 7 below.
[Material 12]
SCF 183 EP-BL 3 manufactured by Super Resin Industry Co., Ltd. was
provided as material 12. The properties of material 12 are shown in
Table 7 below.
[Material 13]
An aluminum alloy A5052 was provided as material 13. The properties
of material 13 are shown in Table 7 below.
[Material 14]
A magnesium alloy AZ31 was provided as material 14. The properties
of material 14 are shown in Table 7 below.
[Material 15]
A titanium alloy Ti-6A1-4V was provided as material 15. The
properties of material 15 are shown in Table 7 below.
[Material 16]
Using a master batch including 90% by mass of a polyamide 6 resin
("AMILAN" (registered trademark) CM1021T manufactured by Toray
Industries, Inc.) and 10% by mass of a polyamide terpolymer resin
composed of polyamide 6/66/610 ("AMILAN" (registered trademark)
CM4000 manufactured by Toray Industries, Inc.), a thermoplastic
resin film having a basis weight of 124 g/m.sup.2 was prepared, and
provided as material 16. The properties of material 16 are shown in
Table 7 below.
TABLE-US-00007 TABLE 7 Material 11 Material 12 Material 13 Material
14 Material 15 Material 16 Material -- CFRP GFRP Al alloy Mg alloy
Ti alloy Ny resin Elastic modulus GPa 60 25 70 45 113 3.5 Linear
expansion 10.sup.-6/.degree. C. 0.3 7 23.6 26 8.2 83 coefficient
Thermal W/m K 3.0 0.3 236.0 159.0 22.0 0.3 conductivity
Example 21
Example 21-(1): Preparation of Bottom Cover
Seven sheets having a predetermined size were cut from material 11.
Among them, four sheets were cut in such a manner that the fiber
direction of a prepreg was parallel to a longitudinal direction (x
direction in FIG. 1), and the other three sheets were cut in such a
manner that the fiber direction was parallel to a lateral direction
(y direction in FIG. 1). In this example, the lateral direction (y
direction) was set to 0.degree., and as shown in FIG. 11, a
laminate including seven prepreg sheets was prepared in such a
manner that prepreg sheets 105a with the fiber direction set to
90.degree. and prepreg sheets 105b with the fiber direction set to
0.degree. were symmetrically laminated.
Here, a press molding apparatus and a pair of molds 106 as shown in
FIG. 12(a) were used, and the resulting laminate 107 was disposed
in a pair of molds 106. Here, the heating platen temperature of the
press molding apparatus was set to 150.degree. C., and as shown in
FIG. 12(b), the molds 106 were moved, and the laminate was
pressurized with the molding pressure kept at 1.0 MPa. After 30
minutes, the molds 106 were opened, and the molded article was
removed from the molds 106. Trimming was performed so that the
rising wall of the resulting molded article had a desired height,
thereby obtaining a bottom cover.
Example 21-(2): Preparation of Top Cover
Except that molds configured to prepare a molded article having a
smooth shape were used, the same procedure as in Example 21-(1) was
carried out to obtain a molded article. Trimming was performed so
that the resulting molded article had a desired size, thereby
obtaining a top cover.
Example 21-(3): Preparation of Reinforcing Structure
Except that molds 106 as shown in FIG. 13 were used, the same
procedure as in Example 21-(1) was carried out to obtain a molded
article. Trimming was performed so that the joining surface of the
resulting molded article had a desired width, thereby obtaining a
reinforcing structure.
Example 21-(4): Preparation of Housing
The members obtained in Examples 21-(1) to 21-(3) were joined using
an adhesive 108 as shown in FIG. 14. The molding conditions and
evaluation results in Example 21 are shown in Table 8 below.
Example 22
Except that a reinforcing structure with a material as described in
Table 8 was molded and used, the same procedure as in Examples
21-(1) to 21-(4) was carried out to obtain a housing. The molding
conditions and evaluation results in Example 22 are shown in Table
8 below.
Example 23
Except that a bottom cover having a size as described in Table 8
was used, the same procedure as in Example 22 was carried out to
obtain a housing. The molding conditions and evaluation results in
Example 23 are shown in Table 8 below.
Example 24
Except that as the reinforcing structure, a material as described
in Table 8 was used, the heating platen temperature was 220.degree.
C., and the molding pressure was 10 MPa, the same procedure as in
Examples 21-(1) to 21-(4) was carried out to obtain a housing. The
molding conditions and evaluation results in Example 24 are shown
in Table 8 below.
Example 25
Except that as the bottom cover, a material as described in Table 9
was used, the heating platen temperature was 200.degree. C., and
the molding pressure was 10 MPa, the same procedure as in Examples
21-(1) to 21-(4) was carried out to obtain a housing. The molding
conditions and evaluation results in Example 25 are shown in Table
9 below.
Example 26
Except that as the bottom cover, a material as described in Table 9
was used, the heating platen temperature was 240.degree. C., and
the molding pressure was 10 MPa, the same procedure as in Examples
21-(1) to 21-(4) was carried out to obtain a housing. The molding
conditions and evaluation results in Example 26 are shown in Table
9 below.
Example 27
Except that a reinforcing structure having a size as described in
Table 9 was molded and used, the same procedure as in Examples
21-(1) to 21-(4) was carried out to obtain a housing. The molding
conditions and evaluation results in Example 27 are shown in Table
9 below.
Example 28
As another reinforcing structure, 25 sheets of material 11 were
laminated so as to have a thickness of 3 mm with prepreg sheets and
90.degree. prepreg sheets being symmetrically laminated in an
alternate manner. In the same manner as in Example 21-(1), the
laminate was heated and pressurized by a press molding apparatus to
obtain a molded article. The resulting molded article was processed
so as to have a height of 7.2 mm, thereby obtaining another
reinforcing structure having a size as shown in Table 9. The
resulting another reinforcing structure was disposed as shown in
FIG. 7, and joined by an adhesive, and subsequently the same
procedure as in Examples 21-(1) to 21-(4) to obtain a housing. The
molding conditions and evaluation results in Example 28 are shown
in Table 9 below.
Example 29
A bottom cover and a reinforcing structure that were obtained in
the same manner as in Examples 21-(1) and 21-(3) were joined to
each other in the following manner: a molten hot melt resin (HM712
manufactured by Cemedine Co., Ltd.) was applied to a joining
portion of the reinforcing structure by a hot melt applicator at
140.degree. C., a reinforcing structure was superposed thereon, a
weight was placed on the reinforcing structure, and this state was
kept for 3 minutes. Except for the method for joining, the same
procedure as in Examples 21-(1) to 21-(4) was carried out to obtain
a housing. The molding conditions and evaluation results in Example
29 are shown in Table 10 below.
Example 30
Example 30-(1): Preparation of Bottom Cover
A film composed of a polyamide copolymer ("AMILAN" (registered
trademark) CM8000 manufactured by Toray Industries, Inc.) and
having a thickness of 50 .mu.m was laminated on a surface to be
joined to the reinforcing structure, thereby obtaining a laminate.
Except that the resulting laminate was used, the same procedure as
in Example 21-(1) was carried out to obtain a bottom cover.
Example 30-(2): Preparation of Top Cover
As in the case of Example 30-(1), a film composed of a polyamide
copolymer ("AMILAN" (registered trademark) CM8000 manufactured by
Toray Industries, Inc.) and having a thickness of 50 .mu.m was
laminated on a surface to be joined to the bottom cover, thereby
obtaining a laminate. Except that the resulting laminate was used,
the same procedure as in Example 21-(2) was carried out to obtain a
top cover.
Example 30-(3): Preparation of Reinforcing Structure
As in the case of Example 30-(1), a film composed of a polyamide
copolymer ("AMILAN" (registered trademark) CM8000 manufactured by
Toray Industries, Inc.) and having a thickness of 50 .mu.m was
laminated on a surface to be joined to the bottom cover, thereby
obtaining a laminate. Except that the resulting laminate was used,
the same procedure as in Example 21-(3) was carried out to obtain a
reinforcing structure.
Example 30-(4): Preparation of Housing
The reinforcing structure obtained in Example 30-(3) was superposed
in a joined form on the bottom cover obtained in Example 30-(1)
were superposed on each other in joined form, a joining tool 109 as
shown in FIG. 15 was provided, and the joined bottom cover and
reinforcing structure were disposed, and heated and pressurized in
a press molding apparatus set so that the joining tool 109 had a
surface temperature of 180.degree. C. After 1 minute, the bottom
cover 2, the reinforcing structure 3 and the joining tool 109 were
taken out from the press molding apparatus, and cooled. After 5
minutes, the joining tool 109 was removed to obtain an integrated
product of the bottom cover 2 and the reinforcing structure 3.
Thereafter, the same procedure as in Examples 21-(1) to 21-(4) was
carried out to obtain a housing. The molding conditions and
evaluation results in Example 30 are shown in Table 10 below.
Example 31
Except that a bottom cover and a top cover were prepared and used
as in the same manner as in Example 30, the same procedure as in
Example 24 was carried out to obtain a material. In the same manner
as in Example 30-(4), members were joined to obtain a housing. The
molding conditions and evaluation results in Example 31 are shown
in Table 10 below.
Example 32
Except that a bottom cover, a top cover and a reinforcing structure
were obtained as in the same manner as in Example 30, the same
procedure as in Example 28 was carried out to obtain a material. In
the same manner as in Example 30-(4), members were joined to obtain
a housing. The molding conditions and evaluation results in Example
32 are shown in Table 10 below.
Examples 33 to 35
Except that a reinforcing structure having a size as in Table 11
was molded and used, the same procedure as in Example 30 was
carried out to obtain a housing. The molding conditions and
evaluation results in Examples 33 to 35 are shown in Table 11
below.
Reference Example 11
Except that a size as described in Table 11 was employed, the same
procedure as in Example 32 was carried out to obtain a bottom cover
and a reinforcing structure. Electronic components were disposed in
a hollow structure S1 formed by the bottom cover and the
reinforcing structure, and a joining portion was joined by an
ultrasonic welding machine in the same manner as in Example 30. In
addition, as a top cover, a liquid crystal display was provided,
and joined to a bottom cover by a double-sided tape. The molding
conditions and evaluation results for the electronic device housing
obtained in Reference Example 11 are shown in Table 11 below.
Comparative Example 11
Except that a reinforcing structure was not used, the same
procedure as in Examples 21-(1) to 21-(4) was carried out to obtain
a housing. The molding conditions and evaluation results in
Comparative Example 11 are shown in Table 12 below.
Comparative Example 12
Except that a laminate obtained by laminating material 11 and
material 12 was used as a material of a bottom cover, the same
procedure as in Comparative Example 11 was carried out to obtain a
housing. The molding conditions and evaluation results in
Comparative Example 12 are shown in Table 12 below.
Comparative Example 13
Comparative Example 13-(1): Preparation of Bottom Cover
A laminate obtained by laminating 10 sheets of material described
in Table 12, a press molding apparatus, and a pair of molds 106 as
shown in FIG. 12(a) were used. The laminate was disposed in a pair
of molds 106. Here, the heating platen temperature of the press
molding apparatus was set to 260.degree. C., and the laminate was
pressurized with the molding pressure kept at 1.0 MPa. After 10
minutes, cooling water was made to pass through the heating plate,
so that cooling was started. After the mold temperature decreased
to 100.degree. C. or lower, the molds 106 were opened, and a molded
article was taken out from the molds 106. Trimming was performed so
that the rising wall of the resulting molded article had a desired
height, thereby obtaining a bottom cover.
Comparative Example 13-(2): Preparation of Reinforcing Structure
and Top Cover
Except that the mold to be used was changed so as to attain a size
as described in Table 12, the same procedure as in Comparative
Example 13-(1) was carried out to obtain a reinforcing structure
and a top cover.
Comparative Example 13-(3): Preparation of Housing
Except that the resulting bottom cover and reinforcing structure
were used, the same procedure as in Example 21-(4) was carried out
to join a bottom cover using an adhesive. The molding conditions
and evaluation results in Comparative Example 13 are shown in Table
12 below.
[Evaluation]
The housings obtained in examples were confirmed to exhibit high
torsional rigidity. Among them, the housing of Example 21 exhibited
very high torsional rigidity, and was also capable of mounting many
electronic devices etc. in a hollow structure because the ratio of
the hollow structure was high. It was confirmed that in Examples 28
and 32, not only torsional rigidity but also deflection rigidity
was exhibited due to the effect of another reinforcing structure.
In addition, Examples 29 to 32 are preferable from the viewpoint of
repair and recycling because the top cover and the reinforcing
structure are joined to each other by thermal welding, and
therefore the joining portion can be disassembled by heating while
high torsional rigidity and deflection rigidity are exhibited.
Examples 30 to 32 are preferable from the viewpoint of weight
reduction because the reinforcing structure and the bottom cover
are bonded directly to each other, and therefore an increase in
weight is smaller as compared to a case where an adhesive or a hot
melt resin is used.
Examples 33 and 34 are intended to reduce the thickness of each
member, and thus contributes to weight reduction and thickness
reduction of the housing while maintaining torsional rigidity. In
addition, Reference Example 11 was provided as a method for using a
housing, where electronic components were disposed in a hollow
structure to prepare an electronic device with a liquid crystal
display used as a top cover. It was confirmed that when the
requirements of the present invention were satisfied, it was
possible to provide a housing exhibiting high torsional rigidity
and deflection rigidity.
On the other hand, the housings of Comparative Examples 11 and 12
had very low resistance to torsion, so that there was the
possibility of damaging internal electronic components. In
Comparative Example 13, a reinforcing structure was used, but the
requirements of the present invention were not satisfied, and it
was impossible to exhibit satisfactory deflection rigidity.
TABLE-US-00008 TABLE 8 Example 21 Example 22 Example 23 Example 24
Bottom cover: Material -- Material 11 Material 11 Material 11
Material 11 Length mm 210 210 210 210 Width mm 300 300 300 300
Height mm 10 10 10 10 Thickness mm 0.8 0.8 0.4 0.8 Projected area
cm.sup.2 630 630 630 630 Volume cm.sup.3 572 572 601 572 Top cover:
Material -- Material 11 Material 11 Material 11 Material 11 Length
mm 210 210 210 210 Width mm 300 300 300 300 Height mm -- -- -- --
Thickness mm 0.8 0.8 0.8 0.8 Projected area cm.sup.2 630 630 630
630 Volume cm.sup.3 -- -- -- -- Reinforcing structure: Material --
Material 12 Material 11 Material 11 Material 13 Length mm 200 200
200 200 Width mm 290 290 290 290 Height mm 8 8 8 8 Angle .degree.
90 90 90 90 Thickness mm 0.8 0.8 0.8 0.6 Overlap width mm 5 5 5 5
Bonding area cm.sup.2 48 48 48 48 Projected area cm.sup.2 580 580
580 580 Volume cm.sup.3 412 412 412 425 Another reinforcing
structure Material -- -- -- -- -- Length mm -- -- -- -- Width mm --
-- -- -- Height mm -- -- -- -- Electronic device housing Projected
area % 92.1 92.1 92.1 92.1 ratio Volume ratio % 72.0 72.0 68.6 74.3
Integration -- Adhesive Adhesive Adhesive Adhesive method Bonding
portion -- Plane Plane Plane Plane Peeling load N/cm.sup.2 1500
1500 1500 1500 (23.degree. C.) Peeling load N/cm.sup.2 700 700 700
700 (200.degree. C.) Evaluation Torsional -- .circle-w/dot.
.circle-w/dot. .circle-w/dot. .circle-w/dot. rigidity Deflection --
.largecircle. .largecircle. .largecircle. .largecircle.
rigidity
TABLE-US-00009 TABLE 9 Example 25 Example 26 Example 27 Example 28
Bottom cover: Material -- Material 11 Material 11 Material 11
Material 11 Length mm 210 210 210 210 Width mm 300 300 300 300
Height mm 10 10 10 10 Thickness mm 0.8 0.8 0.8 0.8 Projected area
cm.sup.2 630 630 630 630 Volume cm.sup.3 572 572 572 572 Top cover:
Material -- Material 11 Material 11 Material 11 Material 11 Length
mm 210 210 210 210 Width mm 300 300 300 300 Height mm -- -- -- --
Thickness mm 0.8 0.8 0.8 0.8 Projected area cm.sup.2 630 630 630
630 Volume cm.sup.3 -- -- -- -- Reinforcing structure: Material --
Material 14 Material 15 Material 12 Material 12 Length mm 200 200
200 200 Width mm 290 290 290 290 Height mm 8 8 8 8 Angle .degree.
90 90 90 90 Thickness mm 0.8 0.2 0.4 0.8 Overlap width mm 5 5 5 5
Bonding area cm.sup.2 48 48 48 48 Projected area cm.sup.2 580 580
580 580 Volume cm.sup.3 412 451 438 412 Another reinforcing
structure Material -- -- -- -- Material 11 Length mm -- -- -- 188
Width mm -- -- -- 3 Height mm -- -- -- 4 Electronic device housing
Projected area % 92.1 92.1 92.1 92.1 ratio Volume ratio % 72.0 78.8
76.5 72.0 Integration -- Adhesive Adhesive Adhesive Adhesive method
Bonding portion -- Plane Plane Plane Plane Peeling load N/cm.sup.2
1500 1500 1500 1500 (23.degree. C.) Peeling load N/cm.sup.2 700 700
700 700 (200.degree. C.) Evaluation Torsional -- .circle-w/dot.
.circle-w/dot. .circle-w/dot. .circle-w/dot. rigidity Deflection --
.largecircle. .largecircle. .largecircle. .circle-w/dot.
rigidity
TABLE-US-00010 TABLE 10 Example 29 Example 30 Example 31 Example 32
Bottom cover: Material -- Material 11 Material 11 Material 11
Material 11 Length mm 210 210 210 210 Width mm 300 300 300 300
Height mm 10 10 10 10 Thickness mm 0.8 0.8 0.8 0.8 Projected area
cm.sup.2 630 630 630 630 Volume cm.sup.3 572 572 572 572 Top cover:
Material -- Material 11 Material 11 Material 11 Material 11 Length
mm 210 210 210 210 Width mm 300 300 300 300 Height mm -- -- -- --
Thickness mm 0.8 0.8 0.8 0.8 Projected area cm.sup.2 630 630 630
630 Volume cm.sup.3 -- -- -- -- Reinforcing structure: Material --
Material 12 Material 12 Material 12 Material 12 Length mm 200 200
200 200 Width mm 290 290 290 290 Height mm 8 8 8 8 Angle .degree.
90 90 90 90 Thickness mm 0.8 0.8 0.6 0.8 Overlap width mm 5 5 5 5
Bonding area cm.sup.2 48 48 48 48 Projected area cm.sup.2 580 580
580 580 Volume cm.sup.3 412 412 425 412 Reinforcing structure:
structure Material -- -- -- -- Material 11 Length mm -- -- -- 188
Width mm -- -- -- 3 Height mm -- -- -- 4 Electronic device housing
Projected area % 92.1 92.1 92.1 92.1 ratio Volume ratio % 72.0 72.0
74.3 72.0 Integration -- Thermal Thermal Thermal Thermal method
welding welding welding welding Bonding portion -- Plane Plane
Plane Plane Peeling load N/cm.sup.2 2000 2500 2500 2500 (23.degree.
C.) Peeling load N/cm.sup.2 50 50 50 50 (200.degree. C.) Evaluation
Torsional -- .circle-w/dot. .circle-w/dot. .circle-w/dot.
.circle-w/dot. rigidity Deflection -- .largecircle. .largecircle.
.largecircle. .circle-w/dot. rigidity
TABLE-US-00011 TABLE 11 Reference Example 33 Example 34 Example 35
Example 11 Bottom cover: Material -- Material 11 Material 11
Material 11 Material 11 Length mm 210 210 210 180 Width mm 300 300
300 230 Height mm 10 10 10 7 Thickness mm 0.8 0.8 0.8 0.8 Projected
area cm.sup.2 630 630 630 414 Volume cm.sup.3 572 572 572 253 Top
cover: Material -- Material 11 Material 11 Material 11 Display
Length mm 210 210 210 210 Width mm 300 300 300 300 Height mm -- --
-- -- Thickness mm 0.8 0.8 0.8 0.8 Projected area cm.sup.2 630 630
630 630 Volume cm.sup.3 -- -- -- -- Reinforcing structure: Material
-- Material 12 Material 12 Material 12 Material 12 Length mm 200
200 200 162 Width mm 290 290 296 215 Height mm 2 3 8 5 Angle
.degree. 90 90 90 90 Thickness mm 0.8 0.8 0.8 0.5 Overlap width mm
5 5 5 5 Bonding area cm.sup.2 48 48 49 37 Projected area cm.sup.3
580 580 610 348 Volume cm.sup.3 412 126 433 155 Reinforcing
structure: structure Material -- -- -- -- -- Length mm -- -- -- --
Width mm -- -- -- -- Height mm -- -- -- -- Electronic device
housing Projected area % 92.1 92.1 96.8 84.1 ratio Volume ratio %
12.0 22.0 75.7 61.4 Integration -- Thermal Thermal Thermal Thermal
method welding welding welding welding Bonding portion -- Plane
Plane Plane Plane Peeling load N/cm.sup.2 2500 2500 2500 2500
(23.degree. C.) Peeling load N/cm.sup.2 50 50 50 50 (200.degree.
C.) Evaluation Torsional -- .largecircle. .largecircle.
.circle-w/dot. .circle-w/dot. rigidity Deflection -- .largecircle.
.largecircle. .largecircle. .largecircle. rigidity
TABLE-US-00012 TABLE 12 Comparative Comparative Comparative Example
11 Example 12 Example 13 Bottom cover: Material -- Material 11
Material 11/ Material 16 Material 12 Length mm 210 210 210 Width mm
300 300 300 Height mm 10 10 10 Thickness mm 0.8 1.6 0.8 Projected
area cm.sup.2 630 630 630 Volume cm.sup.3 572 516 572 Top cover:
Material -- Material 11 Material 11 Material 16 Length mm 210 210
210 Width mm 300 300 300 Height mm -- -- -- Thickness mm 0.8 0.8
0.8 Projected area cm.sup.2 630 630 630 Volume cm.sup.3 -- -- --
Reinforcing structure: Material -- -- -- Material 16 Length mm --
-- 200 Width mm -- -- 290 Height mm -- -- 8 Angle .degree. -- -- 90
Thickness mm -- -- 0.8 Overlap width mm -- -- 5 Bonding area
cm.sup.2 -- -- 48 Projected area cm.sup.2 -- -- 580 Volume cm.sup.3
-- -- 412 Reinforcing structure: structure Material -- -- -- --
Length mm -- -- -- Width mm -- -- -- Height mm -- -- -- Electronic
device housing Projected area % 0.0 0.0 92.1 ratio Volume ratio %
0.0 0.0 72.0 Integration -- -- -- Thermal method welding Bonding
portion -- -- -- Plane Peeling load N/cm.sup.2 -- -- 1500
(23.degree. C.) Peeling load N/cm.sup.2 -- -- 50 (200.degree. C.)
Evaluation Torsional -- X X .largecircle. rigidity Deflection -- X
.largecircle. .DELTA. rigidity
Hereinafter, a fifth aspect of the present invention will be
described in detail by way of examples. However, the present
invention is not limited to the following examples.
<Evaluation and Measurement Methods>
(1) Torsional Rigidity Test
A housing 1 was fixed in a tester in such a manner that one side of
the housing 1 was fixed by a U-shaped fixing tool 100, and the
other side opposed to the fixed side was held by a support tool 101
as shown in FIG. 8(a), the displacement amount of the housing 1 was
then measured when a load of 10 N was applied with a change rate
set to 1.degree./min at an angle .theta. as shown in FIG. 8(b), and
the measured value was defined as a torsional rigidity value of the
housing.
(2) Deflection Rigidity Test
As shown in FIG. 9, the housing was installed in a tester in such a
manner that it was able to apply a load F from the side of a bottom
cover 2 or a top cover 4 to which a reinforcing structure was
joined. "Instron" (registered trademark) Universal Tester Model
4201 (manufactured by Instron Co., Ltd.) was used as a tester. The
deflection amount of the bottom cover 2 or the top cover 4 was
measured when a load of 100 N was applied with the housing 1
pressed at the center position at a cross head speed of 1.0 mm/min
using an indenter 102 having a diameter of 20 mm, and the measured
value was defined as a deflection rigidity value.
(3) Evaluation of Flexural Modulus
In accordance with the specifications in ASTM D-790 (1997), the
flexural moduli of materials to be used for the reinforcing
structure 3, the bottom cover 2 and the top cover 4 were evaluated.
From each of members obtained in examples and comparative examples,
a bending test piece having a width of 25.+-.0.2 mm with a length
set to span L+20.+-.1 mm so that the thickness D and the span L
satisfied the relationship of L/D=16 was cut for the four
directions: 0.degree., +45.degree., -45.degree. and 90.degree.
directions where a certain direction was set to the 0.degree.
direction. In this way, test pieces were prepared. The number of
measurements (n) in each direction was 5, and the average value of
all measured values (n=20) was defined as a flexural modulus.
"Instron" (registered trademark) Universal Tester Model 4201
(manufactured by Instron Co., Ltd.) was used as a tester, a
three-point bending test tool (indenter diameter: 10 mm, fulcrum
diameter: 10 mm) was used, the support span was set to 16 times of
the thickness of the test piece, and the bending elastic modulus
was measured. The test was conducted under the following
conditions: the moisture content of the test piece was 0.1 mass %
or less, the atmospheric temperature was 23.degree. C., and the
humidity was 50% by mass.
(4) Peeling Load Test of Reinforcing Structure (23.degree. C. and
200.degree. C.)
The peeling load of the reinforcing structure was evaluated in
accordance with "Testing methods for tensile strength of adhesive
bonds" specified in JIS K6849 (1994). As test pieces in this test,
housings obtained in examples and comparative examples were used.
Here, for measuring the peeling strength of the reinforcing
structure, evaluation was performed in a state in which there was
not a top cover or bottom cover to which the reinforcing structure
was not joined (before the reinforcing structure was joined).
Specifically, as shown in FIG. 10, the bottom cover 2 or the top
cover 4 of the housing 1 was fixed by a fixing tool 103, and the
reinforcing structure 3 was fixed by a tensile tool 104. A tensile
load F was applied while each member was fixed, and evaluation was
performed until the reinforcing structure 3 was peeled off, or the
tensile tool 104 was detached from the reinforcing structure 3. The
bonding area here was calculated by measuring the width and length
of the joining surface of the reinforcing structure 3 before
joining. When joining was partially performed, the areas thereof
were measured, and summed to determine a joining area. The peeling
load of the reinforcing structure 3 was calculated from the
resulting tensile load value and joining area. For the peeling load
of the reinforcing structure 3 at 200.degree. C., the housing 1 was
placed in a thermostat together with the fixing tool, and the
atmospheric temperature in the thermostat was elevated to
200.degree. C. After elevation of the temperature, this state was
maintained for 10 minutes, and a tensile load was then applied in
the same manner as in the peeling load test of the reinforcing
structure 3, and evaluation was performed.
(5) Evaluation of Linear Expansion Coefficient of Each Member
The linear expansion coefficient of each member was evaluated by
referring to "Testing method for linear thermal expansion
coefficient of plastics by thermomechanical analysis" as specified
in JIS K 7197 (1991). As test pieces in this evaluation, members
obtained in examples and comparative examples were used. Here, the
thickness was set to the thickness of each member, and processing
was performed so that the length of one side was 5 mm, thereby
preparing a test piece. The number of measurements was 5 (n=5), and
the average value of the measurements was defined as a linear
expansion coefficient of each member.
(6) Heat Cycle Test
The resulting housing was placed in a tester capable of controlling
the inside atmospheric temperature, and programmed operation was
performed. As programmed operation conditions, the minimum
temperature was -25.degree. C., the maximum temperature was
85.degree. C., and after reaching each temperature, the temperature
was maintained for 10 minutes, after which the temperature was
changed at a rate of 1.degree. C./min. A cycle of reaching the
maximum temperature from the minimum temperature and reaching the
minimum temperature from the maximum temperature was repeated ten
times, followed by checking whether or not delamination or warpage
occurred in the housing. A sample was rated o when there was no
change from the state before the test, and a sample was rated x
when delamination or warpage occurred.
<Materials Used>
Materials used for evaluation are shown below.
[Material 21]
"TORAYCA" Prepreg P3252S-12 (manufactured by Toray Industries,
Inc.) was provided as material 21. The properties of material 21
are shown in Table 13 below.
[Material 22]
SCF183 EP-BL3 manufactured by SUPER RESIN. Inc. was provided as
material 22. The properties of material 22 are shown in Table 13
below.
[Material 23]
An aluminum alloy A5052 was provided as material 23. The properties
of material 23 are shown in Table 13 below.
[Material 24]
A magnesium alloy AZ31 was provided as material 24. The properties
of material 24 are shown in Table 13 below.
[Material 25]
Using a master batch including 90% by mass of a polyamide 6 resin
("AMILAN" (registered trademark) CM1021T manufactured by Toray
Industries, Inc.) and 10% by mass of a polyamide terpolymer resin
composed of polyamide 6/66/610 ("AMILAN" (registered trademark)
CM4000 manufactured by Toray Industries, Inc.), a thermoplastic
resin film having a basis weight of 124 g/m.sup.2 was prepared, and
provided as material 25. The properties of material 25 are shown in
Table 13 below.
[Material 26]
Resin pellets of a polycarbonate resin ("Iupilon" (registered
trademark) H-4000'' manufactured by Mitsubishi Engineering-Plastics
Corporation) were provided. Before molding, the resin pellets were
dried for 5 hours using a hot air circulating dryer with the inside
temperature set to 120.degree. C. The properties of material 26 are
shown in Table 13 below.
TABLE-US-00013 TABLE 13 Material 21 Material 22 Material 23
Material 24 Material 25 Material 26 Material -- CFRP GFRP Al alloy
Mg alloy Ny alloy PC resin Elastic modulus GPa 60 25 70 45 3.5 2.3
Linear expansion 10.sup.-6/.degree. C. 0.3 7 23.6 26 83 65
coefficient Thermal W/m K 3.0 0.3 236.0 159.0 0.3 0.2
conductivity
Example 41
Example 41-(1): Preparation of Bottom Cover
Seven sheets having a predetermined size were cut from material 21.
Among them, four sheets were cut in such a manner that the fiber
direction of a prepreg was parallel to a longitudinal direction (x
direction in FIG. 1), and the other three sheets were cut in such a
manner that the fiber direction was parallel to a lateral direction
(y direction in FIG. 1). In this example, the lateral direction (y
direction) was set to 0.degree., and as shown in FIG. 11, a
laminate including seven prepreg sheets was prepared in such a
manner that prepreg sheets 105a with the fiber direction set to
90.degree. and prepreg sheets 105b with the fiber direction set to
0.degree. were symmetrically laminated.
Here, a press molding apparatus and a pair of molds 106 as shown in
FIG. 12(a) were used, and the resulting laminate 107 was disposed
in a pair of molds 106. Here, the heating platen temperature of the
press molding apparatus was set to 150.degree. C., and as shown in
FIG. 12(b), the molds 106 were moved, and the laminate was
pressurized with the molding pressure kept at 1.0 MPa. After 30
minutes, the molds 106 were opened, and the molded article was
removed from the molds 106. Trimming was performed so that the
rising wall of the resulting molded article had a desired height,
thereby obtaining a bottom cover.
Example 41-(2): Preparation of Top Cover
Except that molds configured to prepare a molded article having a
smooth shape were used, the same procedure as in Example 41-(1) was
carried out to obtain a molded article. Trimming was performed so
that the resulting molded article had a desired size, thereby
obtaining a top cover.
Example 41-(3): Preparation of Reinforcing Structure
Except that molds 106 as shown in FIG. 13 were used, the same
procedure as in Example 41-(1) was carried out to obtain a molded
article. Trimming was performed so that the joining surface of the
resulting molded article had a desired width, thereby obtaining a
reinforcing structure.
Example 41-(4): Preparation of Housing
The members obtained in Examples 41-(1) to 41-(3) were joined using
an adhesive 108 as shown in FIG. 14. The molding conditions and
evaluation results in Example 41 are shown in Table 14 below.
Example 42
Except that a material as described in Table 14 was used, the same
procedure as in Examples 41-(1) to 41-(4) was carried out to obtain
a housing. The molding conditions and evaluation results in Example
42 are shown in Table 14 below.
Example 43
Except that a material as described in Table 14 was used, the
heating platen temperature was 220.degree. C., and the molding
pressure was 10 MPa, the same procedure as in Examples 41-(1) to
41-(4) was carried out to obtain a housing. The molding conditions
and evaluation results in Example 43 are shown in Table 14
below.
Example 44
Using an injection molding machine, a material as described in
Table 14 was subjected to injection molding with the cylinder
temperature and the mold temperature set to 260.degree. C. and
80.degree. C., respectively, thereby obtaining each member. Using
the resulting members, the same procedure as in Example 41-(4) was
carried out to obtain a housing. The molding conditions and
evaluation results in Example 44 are shown in Table 14 below.
Example 45
A bottom cover and a top cover were prepared in the same manner as
in Example 43, and a reinforcing structure was prepared in the same
manner as in Example 44. Using the resulting members, the same
procedure as in Example 41-(4) was carried out to obtain a housing.
The molding conditions and evaluation results in Example 45 are
shown in Table 15 below.
Example 46
A bottom cover and a top cover were prepared in the same manner as
in Example 43, and a reinforcing structure was prepared in the same
manner as in Example 42. Using the resulting members, the same
procedure as in Example 41-(4) was carried out to obtain a housing.
The molding conditions and evaluation results in Example 46 are
shown in Table 15 below.
Example 47
A bottom cover and a reinforcing structure that were obtained in
the same manner as in Examples 41-(1) and 41-(3) were joined to
each other in the following manner: a molten hot melt resin (HM712
manufactured by Cemedine Co., Ltd.) was applied to a joining
portion of the reinforcing structure by a hot melt applicator at
140.degree. C., a reinforcing structure was superposed thereon, a
weight was placed on the reinforcing structure, and this state was
kept for 3 minutes. Except for the method for joining, the same
procedure as in Examples 41-(1) to 41-(4) was carried out to obtain
a housing. The molding conditions and evaluation results in Example
47 are shown in Table 15 below.
Example 48
A bottom cover and a reinforcing structure that were obtained in
the same manner as in Examples 42-(1) and 42-(3) were joined to
each other in the following manner: a molten hot melt resin (HM712
manufactured by Cemedine Co., Ltd.) was applied to a joining
portion of the reinforcing structure by a hot melt applicator at
140.degree. C., a reinforcing structure was superposed thereon, a
weight was placed on the reinforcing structure, and this state was
kept for 3 minutes. Except for the method for joining, the same
procedure as in Examples 42-(1) to 42-(4) was carried out to obtain
a housing. The molding conditions and evaluation results in Example
48 are shown in Table 15 below.
Example 49
A bottom cover and a reinforcing structure that were obtained in
the same manner as in Examples 43-(1) and 43-(3) were joined to
each other in the following manner: a molten hot melt resin (HM712
manufactured by Cemedine Co., Ltd.) was applied to a joining
portion of the reinforcing structure by a hot melt applicator at
140.degree. C., a reinforcing structure was superposed thereon, a
weight was placed on the reinforcing structure, and this state was
kept for 3 minutes. Except for the method for joining, the same
procedure as in Examples 43-(1) to 43-(4) was carried out to obtain
a housing. The molding conditions and evaluation results in Example
49 are shown in Table 16 below.
Example 50
A bottom cover and a reinforcing structure that were obtained in
the same manner as in Examples 44-(1) and 44-(3) were joined to
each other in the following manner: a molten hot melt resin (HM712
manufactured by Cemedine Co., Ltd.) was applied to a joining
portion of the reinforcing structure by a hot melt applicator at
140.degree. C., a reinforcing structure was superposed thereon, a
weight was placed on the reinforcing structure, and this state was
kept for 3 minutes. Except for the method for joining, the same
procedure as in Examples 44-(1) to 44-(4) was carried out to obtain
a housing. The molding conditions and evaluation results in Example
50 are shown in Table 16 below.
Example 51
A bottom cover and a reinforcing structure that were obtained in
the same manner as in Examples 45-(1) and 45-(3) were joined to
each other in the following manner: a molten hot melt resin (HM712
manufactured by Cemedine Co., Ltd.) was applied to a joining
portion of the reinforcing structure by a hot melt applicator at
140.degree. C., a reinforcing structure was superposed thereon, a
weight was placed on the reinforcing structure, and this state was
kept for 3 minutes. Except for the method for joining, the same
procedure as in Examples 45-(1) to 45-(4) was carried out to obtain
a housing. The molding conditions and evaluation results in Example
51 are shown in Table 16 below.
Example 52
A bottom cover and a top cover were prepared in the same manner as
in Example 44. Using an injection molding machine, a material as
described in Table 16 was subjected to injection molding with the
cylinder temperature and the mold temperature set to 280.degree. C.
and 100.degree. C., respectively, thereby obtaining a reinforcing
structure. The resulting bottom cover and reinforcing structure
were joined to each other in the following manner: a molten hot
melt resin (HM712 manufactured by Cemedine Co., Ltd.) was applied
to a joining portion of the reinforcing structure by a hot melt
applicator at 140.degree. C., a reinforcing structure was
superposed thereon, a weight was placed on the reinforcing
structure, and this state was kept for 3 minutes. Except for the
method for joining, the same procedure as in Examples 50-(1) to
50-(4) was carried out to obtain a housing. The molding conditions
and evaluation results in Example 52 are shown in Table 16
below.
Example 53
Each member was obtained in the same manner as in Example 46. The
resulting bottom cover and reinforcing structure were joined to
each other in the following manner: a molten hot melt resin (HM712
manufactured by Cemedine Co., Ltd.) was applied to a joining
portion of the reinforcing structure by a hot melt applicator at
140.degree. C., a reinforcing structure was superposed thereon, a
weight was placed on the reinforcing structure, and this state was
kept for 3 minutes. Except for the method for joining, the same
procedure as in Examples 46-(1) to 46-(4) was carried out to obtain
a housing. The molding conditions and evaluation results in Example
53 are shown in Table 17 below.
Example 54
Using an injection molding machine, material 25 was subjected to
injection molding with the cylinder temperature and the mold
temperature set to 260.degree. C. and 80.degree. C., respectively,
thereby obtaining a 3 mm-thick plate-like molded article as another
reinforcing structure. The resulting molded article was processed
so as to have a height of 7.2 mm, thereby obtaining another
reinforcing structure having a size as shown in Table 17. The
resulting another reinforcing structure was disposed as shown in
FIG. 7, and joined by an adhesive, and subsequently the same
procedure as in Examples 50-(1) to 50-(4) to obtain a housing. The
molding conditions and evaluation results in Example 54 are shown
in Table 17 below.
Example 55
A bottom cover and a reinforcing structure that were obtained in
the same manner as in Examples 50-(1) and 50-(2) were joined to
each other by an ultrasonic welding method. Except for the method
for joining, the same procedure as in Examples 50-(1) to 50-(4) was
carried out to obtain a housing. The molding conditions and
evaluation results in Example 55 are shown in Table 17 below.
Example 56
Example 56-(1): Preparation of Bottom Cover
A film composed of a polyamide copolymer ("AMILAN" (registered
trademark) CM8000 manufactured by Toray Industries, Inc.) and
having a thickness of 50 .mu.m was laminated on a surface to be
joined to the reinforcing structure, thereby obtaining a laminate.
Except that the resulting laminate was used, the same procedure as
in Example 41-(1) was carried out to obtain a bottom cover.
Example 56-(2): Preparation of Top Cover
As in the case of Example 56-(1), a film composed of a polyamide
copolymer ("AMILAN" (registered trademark) CM8000 manufactured by
Toray Industries, Inc.) and having a thickness of 50 .mu.m was
laminated on a surface to be joined to the bottom cover, thereby
obtaining a laminate. Except that the resulting laminate was used,
the same procedure as in Example 41-(2) was carried out to obtain a
top cover.
Example 56-(3): Preparation of Reinforcing Structure
As in the case of Example 56-(1), a film composed of a polyamide
copolymer ("AMILAN" (registered trademark) CM8000 manufactured by
Toray Industries, Inc.) and having a thickness of 50 .mu.m was
laminated on a surface to be joined to the bottom cover, thereby
obtaining a laminate. Except that the resulting laminate was used,
the same procedure as in Example 41-(3) was carried out to obtain a
reinforcing structure.
Example 56-(4): Preparation of Housing
The reinforcing structure obtained in Example 56-(3) was superposed
in a joined form on the bottom cover obtained in Example 56-(1)
were superposed on each other in joined form, a joining tool 109 as
shown in FIG. 15 was provided, and the joined bottom cover and
reinforcing structure were disposed, and heated and pressurized in
a press molding apparatus set so that the joining tool 109 had a
surface temperature of 180.degree. C. After 1 minute, the bottom
cover 2, the reinforcing structure 3 and the joining tool 109 were
taken out from the press molding apparatus, and cooled. After 5
minutes, the joining tool 109 was removed to obtain an integrated
product of the bottom cover 2 and the reinforcing structure 3.
Thereafter, the top cover 4 was joined using an adhesive in the
same manner as in Example 41-(4). The molding conditions and
evaluation results in Example 56 are shown in Table 17 below.
Example 57
Except that a material as described in Table 18 was used, the same
procedure as in Examples 56-(1) to 56-(4) was carried out to obtain
a housing. The molding conditions and evaluation results in Example
57 are shown in Table 18 below.
Example 58
Except that a reinforcing structure obtained in the same manner as
in Example 43 was used, the same procedure as in Example 57 was
carried out to obtain a housing. The molding conditions and
evaluation results in Example 58 are shown in Table 18 below.
Example 59
Except that the heating platen temperature was 200.degree. C., the
same procedure as in Example 43 was carried out to obtain a bottom
cover and a top cover. In addition, a reinforcing structure was
obtained in the same manner as in Example 57. Except that the
resulting members were used, the same procedure as in Example 56
was carried out to obtain a housing. The molding conditions and
evaluation results in Example 59 are shown in Table 18 below.
Example 60
A bottom cover and a top cover were obtained in the same manner as
in Example 43. In addition, a reinforcing structure was obtained in
the same manner as in Example 57. Except that the resulting members
were used, the same procedure as in Example 56 was carried out to
obtain a housing. The molding conditions and evaluation results in
Example 60 are shown in Table 18 below.
Examples 61 to 63
Except that a size as described in Table 19 was employed, the same
procedure as in Example 60 was carried out to obtain each member.
Using the resulting members, the same procedure as in Example 56
was carried out to obtain a housing. The molding conditions and
evaluation results in Examples 61 and 63 are shown in Table 19
below.
Reference Example 21
Except that a size as described in Table 19 was employed, the same
procedure as in Example 60 was carried out to obtain a bottom cover
and a reinforcing structure. Electronic components were disposed in
a hollow structure S1 formed by the bottom cover and the
reinforcing structure, and a joining portion was joined by an
ultrasonic welding machine in the same manner as in Example 60. In
addition, as a top cover, a liquid crystal display was provided,
and joined to a bottom cover by a double-sided tape. The molding
conditions and evaluation results in Reference Example 21 are shown
in Table 19 below.
Comparative Example 21
A bottom cover and a top cover were obtained in the same manner as
in Example 41. In addition, a reinforcing structure was obtained in
the same manner as in Example 44. Except that the resulting members
were used, the same procedure as in Examples 41-(1) to 41-(4) was
carried out to obtain a housing. The molding conditions and
evaluation results in Comparative Example 21 are shown in Table 20
below.
[Evaluation]
It was confirmed that in the housings obtained in examples, either
delamination or warpage did not occur between the reinforcing
structure and the bottom cover even after the heat cycle test, and
thus these housings were excellent in dimensional stability. In
addition, it was confirmed that these housings also had high
torsional rigidity. In particular, Examples 47 to 63 are preferable
from the viewpoint of repair and recycling because the top cover
and the reinforcing structure are joined to each other by thermal
welding, and therefore the reinforcing structure can be
disassembled by heating while high torsional rigidity and
deflection rigidity are exhibited. Examples 56 to 63 are preferable
from the viewpoint of weight reduction because the reinforcing
structure and the bottom cover are bonded directly to each other,
and therefore an increase in weight is smaller as compared to a
case where an adhesive or a hot melt resin is used. It was
confirmed that in Example 54, not only torsional rigidity but also
deflection rigidity was exhibited due to the effect of another
reinforcing structure.
In examples where a glass fiber-reinforced composite material, a
carbon fiber-reinforced composite material or a metal material
having high dynamic properties was used for the bottom cover, not
only high torsional rigidity but also deflection rigidity was
exhibited. In addition, the metal material has a high thermal
conductivity, and is therefore preferable from the viewpoint of
thermal characteristics. In examples where a resin or a glass
fiber-reinforced composite material was used for the bottom cover
are preferable from the viewpoint of not only exhibiting high
torsional rigidity but also enabling radio wave communication
because the bottom cover has electromagnetic wave permeability. It
was confirmed that in examples where only a resin material was
used, the housing had poor deflection rigidity, but exhibited
torsional rigidity. In addition, Reference Example 21 was provided
as a method for using a housing, where electronic components were
disposed in a hollow structure to prepare an electronic device with
a liquid crystal display used as atop cover. It was confirmed that
when the requirements of the present invention were satisfied, it
was possible to provide an electronic device exhibiting high
torsional rigidity and deflection rigidity.
On the other hand, Comparative Example 21 exhibited torsional
rigidity and deflection rigidity, but after the heat cycle test,
the reinforcing structure and the bottom cover were peeled off from
each other. Such a housing can be used only in a limited
environment, and does not meet requests from the market.
TABLE-US-00014 TABLE 14 Example 41 Example 42 Example 43 Example 44
Bottom cover: Material -- Material 21 Material 22 Material 23
Material 25 Length mm 210 210 210 210 Width mm 300 300 300 300
Height mm 10 10 10 10 Thickness mm 0.8 0.8 0.6 0.8 Projected area
cm.sup.2 630 630 630 630 Volume cm.sup.3 572 572 586 572 Top cover:
Material -- Material 21 Material 22 Material 23 Material 25 Length
mm 210 210 210 210 Width mm 300 300 300 300 Height mm -- -- -- --
Thickness mm 0.8 0.8 0.8 0.8 Projected area cm.sup.2 630 630 630
630 Volume cm.sup.3 -- -- -- -- Reinforcing structure: Material --
Material 21 Material 22 Material 23 Material 25 Length mm 200 200
200 200 Width mm 290 290 290 290 Height mm 8 8 8 8 Angle .degree.
90 90 90 90 Thickness mm 0.8 0.8 0.8 0.8 Overlap width mm 5 5 5 5
Bonding area cm.sup.2 48 48 48 48 Projected area cm.sup.2 580 580
580 580 Volume cm.sup.3 412 412 412 412 Reinforcing structure:
structure Material -- -- -- -- -- Length mm -- -- -- -- Width mm --
-- -- -- Height mm -- -- -- -- Electronic device housing Projected
area % 92.1 92.1 92.1 92.1 ratio Volume ratio % 72.0 72.0 70.2 72.0
Integration -- Adhesive Adhesive Adhesive Adhesive method Bonding
portion -- Plane Plane Plane Plane Peeling load N/cm.sup.2 1500
1500 1500 1500 (23.degree. C.) Peeling load N/cm.sup.2 700 700 700
700 (200.degree. C.) Linear expansion -- 1.0 1.0 1.0 1.0
coefficient ratio Evaluation Torsional -- .circle-w/dot.
.circle-w/dot. .circle-w/dot. .largecircle. rigidity Deflection --
.largecircle. .largecircle. .largecircle. .DELTA. rigidity Heat
cycle test -- .largecircle. .largecircle. .largecircle.
.largecircle.-
TABLE-US-00015 TABLE 15 Example 45 Example 46 Example 47 Example 48
Bottom cover: Material -- Material 23 Material 23 Material 21
Material 22 Length mm 210 210 210 210 Width mm 300 300 300 300
Height mm 10 10 10 10 Thickness mm 0.6 0.6 0.8 0.8 Projected area
cm.sup.2 630 630 630 630 Volume cm.sup.3 586 586 572 572 Top cover:
Material -- Material 23 Material 23 Material 21 Material 22 Length
mm 210 210 210 210 Width mm 300 300 300 300 Height mm -- -- -- --
Thickness mm 0.8 0.8 0.8 0.8 Projected area cm.sup.2 630 630 630
630 Volume cm.sup.3 -- -- -- -- Reinforcing structure: Material --
Material 25 Material 22 Material 21 Material 22 Length mm 200 200
200 200 Width mm 290 290 290 290 Height mm 8 8 8 8 Angle .degree.
90 90 90 90 Thickness mm 0.8 0.8 0.8 0.8 Overlap width mm 5 5 5 5
Bonding area cm.sup.2 48 48 48 48 Projected area cm.sup.2 580 580
580 580 Volume cm.sup.3 412 412 412 412 Reinforcing structure:
structure Material -- -- -- -- -- Length mm -- -- -- -- Width mm --
-- -- -- Height mm -- -- -- -- Electronic device housing Projected
area % 92.1 92.1 92.1 92.1 ratio Volume ratio % 70.2 70.2 72.0 72.0
Integration -- Adhesive Adhesive Thermal Thermal method welding
welding Bonding portion -- Plane Plane Plane Plane Peeling load
N/cm.sup.2 1500 1500 2000 2000 (23.degree. C.) Peeling load
N/cm.sup.2 700 700 100 100 (200.degree. C.) Linear expansion -- 0.3
3.4 1.0 1.0 coefficient ratio Evaluation Torsional --
.circle-w/dot. .circle-w/dot. .circle-w/dot. .circle-w/dot.
rigidity Deflection -- .largecircle. .largecircle. .largecircle.
.largecircle. rigidity Heat cycle test -- .largecircle.
.largecircle. .largecircle. .largecircle.-
TABLE-US-00016 TABLE 16 Example 49 Example 50 Example 51 Example 52
Bottom cover: Material -- Material 23 Material 25 Material 23
Material 25 Length mm 210 210 210 210 Width mm 300 300 300 300
Height mm 10 10 10 10 Thickness mm 0.6 0.8 0.6 0.8 Projected area
cm.sup.2 630 630 630 630 Volume cm.sup.3 586 572 586 572 Top cover:
Material -- Material 23 Material 25 Material 23 Material 25 Length
mm 210 210 210 210 Width mm 300 300 300 300 Height mm -- -- -- --
Thickness mm 0.8 0.8 0.8 0.8 Projected area cm.sup.2 630 630 630
630 Volume cm.sup.3 -- -- -- -- Reinforcing structure: Material --
Material 23 Material 25 Material 25 Material 26 Length mm 200 200
200 200 Width mm 290 290 290 290 Height mm 8 8 8 8 Angle .degree.
90 90 90 90 Thickness mm 0.8 0.8 0.8 0.8 Overlap width mm 5 5 5 5
Bonding area cm.sup.2 48 48 48 48 Projected area cm.sup.2 580 580
580 580 Volume cm.sup.3 412 412 412 412 Another reinforcing
structure Material -- -- -- -- -- Length mm -- -- -- -- Width mm --
-- -- -- Height mm -- -- -- -- Electronic device housing Projected
area % 92.1 92.1 92.1 92.1 ratio Volume ratio % 70.2 72.0 70.2 72.0
Integration -- Thermal Thermal Thermal Thermal method welding
welding welding welding Bonding portion -- Plane Plane Plane Plane
Peeling load N/cm.sup.2 2000 2000 2000 2000 (23.degree. C.) Peeling
load N/cm.sup.2 50 50 50 50 (200.degree. C.) Linear expansion --
1.0 1.0 0.3 1.7 coefficient ratio Evaluation Torsional --
.circle-w/dot. .largecircle. .circle-w/dot. .largecircle. rigidity
Deflection -- .largecircle. .DELTA. .largecircle. .DELTA. rigidity
Heat cycle test -- .largecircle. .largecircle. .largecircle.
.largecircle.-
TABLE-US-00017 TABLE 17 Example 53 Example 54 Example 55 Example 56
Bottom cover: Material -- Material 23 Material 25 Material 25
Material 21 Length mm 210 210 210 210 Width mm 300 300 300 300
Height mm 10 10 10 10 Thickness mm 0.6 0.8 0.8 0.8 Projected area
cm.sup.2 630 630 630 630 Volume cm.sup.3 586 572 572 572 Top cover:
Material -- Material 23 Material 25 Material 25 Material 21 Length
mm 210 210 210 210 Width mm 300 300 300 300 Height mm -- -- -- --
Thickness mm 0.8 0.8 0.8 0.8 Projected area cm.sup.2 630 630 630
630 Volume cm.sup.3 -- -- -- -- Reinforcing structure: Material --
Material 22 Material 25 Material 25 Material 21 Length mm 200 200
200 200 Width mm 290 290 290 290 Height mm 8 8 8 8 Angle .degree.
90 90 90 90 Thickness mm 0.8 0.8 0.8 0.8 Overlap width mm 5 5 5 5
Bonding area cm.sup.2 48 48 48 48 Projected area cm.sup.2 580 580
580 580 Volume cm.sup.3 412 412 412 412 Another reinforcing
structure Material -- -- Material 25 -- -- Length mm -- 188 -- --
Width mm -- 3 -- -- Height mm -- 4 -- -- Electronic device housing
Projected area % 92.1 92.1 92.1 92.1 ratio Volume ratio % 70.2 72.0
72.0 72.0 Integration -- Thermal Thermal Thermal Thermal method
welding welding welding welding Bonding portion -- Plane Plane
Plane Plane Peeling load N/cm.sup.2 2000 2000 1500 2000 (23.degree.
C.) Peeling load N/cm.sup.2 50 50 50 50 (200.degree. C.) Linear
expansion -- 3.4 1.0 0.3 1.7 coefficient ratio Evaluation Torsional
-- .circle-w/dot. .largecircle. .largecircle. .circle-w/dot.
rigidity Deflection -- .largecircle. .DELTA. .largecircle.
.largecircle. rigidity Heat cycle test -- .largecircle.
.largecircle. .largecircle. .largecircle.-
TABLE-US-00018 TABLE 18 Example 57 Example 58 Example 59 Example 60
Bottom cover: Material -- Material 22 Material 22 Material 24
Material 23 Length mm 210 210 210 210 Width mm 300 300 300 300
Height mm 10 10 10 10 Thickness mm 0.8 0.8 0.8 0.8 Projected area
cm.sup.2 630 630 630 630 Volume cm.sup.3 572 572 572 586 Top cover:
Material -- Material 22 Material 22 Material 24 Material 23 Length
mm 210 210 210 210 Width mm 300 300 300 300 Height mm -- -- -- --
Thickness mm 0.8 0.8 0.8 0.8 Projected area cm.sup.2 630 630 630
630 Volume cm.sup.3 -- -- -- -- Reinforcing structure: Material --
Material 22 Material 23 Material 22 Material 22 Length mm 200 200
200 200 Width mm 290 290 290 290 Height mm 8 8 8 8 Angle .degree.
90 90 90 90 Thickness mm 0.8 0.6 0.8 0.8 Overlap width mm 5 5 5 5
Bonding area cm.sup.2 48 48 48 48 Projected area cm.sup.2 580 580
580 580 Volume cm.sup.3 412 425 412 412 Another reinforcing
structure Material -- -- -- -- -- Length mm -- -- -- -- Width mm --
-- -- -- Height mm -- -- -- -- Electronic device housing Projected
area % 92.1 92.1 92.1 92.1 ratio Volume ratio % 72.0 74.3 72.0 70.2
Integration -- Thermal Thermal Thermal Thermal method welding
welding welding welding Bonding portion -- Plane Plane Plane Plane
Peeling load N/cm.sup.2 2500 2500 2500 2500 (23.degree. C.) Peeling
load N/cm.sup.2 50 50 50 50 (200.degree. C.) Linear expansion --
1.0 0.3 3.7 3.4 coefficient ratio Evaluation Torsional --
.circle-w/dot. .circle-w/dot. .largecircle. .circle-w/dot. rigidity
Deflection -- .largecircle. .largecircle. .largecircle.
.largecircle. rigidity Heat cycle test -- .largecircle.
.largecircle. .largecircle. .largecircle.-
TABLE-US-00019 TABLE 19 Reference Example 61 Example 62 Example 63
Example 21 Bottom cover: Material -- Material 23 Material 23
Material 23 Material 23 Length mm 210 210 210 210 Width mm 300 300
300 230 Height mm 10 10 10 7 Thickness mm 0.8 0.8 0.8 0.8 Projected
area cm.sup.2 630 630 630 414 Volume cm.sup.3 572 572 572 253 Top
cover: Material -- Material 23 Material 23 Material 23 Display
Length mm 210 210 210 210 Width mm 300 300 300 300 Height mm -- --
-- -- Thickness mm 0.8 0.8 0.8 0.8 Projected area cm.sup.2 630 630
630 630 Volume cm.sup.3 -- -- -- -- Reinforcing structure: Material
-- Material 22 Material 22 Material 22 Material 22 Length mm 206
200 206 162 Width mm 296 290 296 215 Height mm 3 3 8 5 Angle
.degree. 90 90 90 90 Thickness mm 0.8 0.6 0.8 0.8 Overlap width mm
5 5 5 5 Bonding area cm.sup.2 49 48 49 37 Projected area cm.sup.2
610 580 610 348.3 Volume cm.sup.3 132 126 433 155 Another
reinforcing structure Material -- -- -- -- -- Length mm -- -- -- --
Width mm -- -- -- -- Height mm -- -- -- -- Electronic device
housing Projected area % 96.8 92.1 96.8 84.1 ratio Volume ratio %
23.1 22.0 75.7 61.4 Integration -- Thermal Thermal Thermal Thermal
method welding welding welding welding Bonding portion -- Plane
Plane Plane Plane Peeling load N/cm.sup.2 2500 2500 2500 2500
(23.degree. C.) Peeling load N/cm.sup.2 50 50 50 50 (200.degree.
C.) Linear expansion -- 3.4 3.4 3.4 3.4 coefficient ratio
Evaluation Torsional -- .largecircle. .largecircle. .circle-w/dot.
.circle-w/dot. rigidity Deflection -- .largecircle. .largecircle.
.largecircle. .largecircle. rigidity Heat cycle test --
.largecircle. .largecircle. .largecircle. .largecircle.-
TABLE-US-00020 TABLE 20 Comparative Example 21 Bottom cover:
Material -- Material 21 Length mm 210 Width mm 300 Height mm 10
Thickness mm 0.8 Projected area cm.sup.2 630 Volume cm.sup.3 572
Top cover: Material -- Material 21 Length mm 210 Width mm 300
Height mm -- Thickness mm 0.8 Projected area cm.sup.2 630 Volume
cm.sup.3 -- Reinforcing structure: Material -- Material 25 Length
mm 200 Width mm 290 Height mm 8 Angle .degree. 90 Thickness mm 0.8
Overlap width mm 5 Bonding area cm.sup.2 48 Projected area cm.sup.2
580 Volume cm.sup.3 412 Another reinforcing structure Material --
-- Length mm -- Width mm -- Height mm -- Electronic device housing
Projected area % 92.1 ratio Volume ratio % 72.0 Integration --
Adhesive method Bonding portion -- Plane Peeling load N/cm.sup.2
1500 (23.degree. C.) Peeling load N/cm.sup.2 700 (200.degree. C.)
Linear expansion -- 0.004 coefficient ratio Evaluation Torsional --
.DELTA. rigidity Deflection -- .largecircle. rigidity Heat cycle
test -- X
INDUSTRIAL APPLICABILITY
According to the present invention, there can be provided a housing
having improved torsional rigidity and deflection rigidity while
attaining thickness reduction and weight reduction. In addition,
according to the present invention, there can be provided a housing
having improved torsional rigidity while attaining thickness
reduction, weight reduction and improvement of portability. In
addition, according to the present invention, there can be provided
a housing having high torsional rigidity and improved dimensional
stability.
DESCRIPTION OF REFERENCE SIGNS
1: Housing 2: Bottom cover 3: Reinforcing structure 4: Top cover 5:
Another reinforcing structure 21: Flat portion 22: Rising wall
member 31: Flat portion 32: Rising wall member 33: Joining
portion
* * * * *